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Issued, November, 1928
UNITED STATES DEPARTMENT OF AGRICULTURE
BUREAU OF AGRICULTURAL ECONOMICS
NILS A. OLSEN, Chief
ATLAS
OF
AMERICAN AGRICULTURE
Prepared under the Supervision of 0. E. BAKER, Senior Agricultural Economist
PART II
G L I M AT E
SECTION B
TEMPERATURE, SUNSHINE, AND WIND
Contribution from the U. S. Weather Bureau, CHARLES F. MARVIN, Chief
BY
JOSEPH B. KINCER
Senior Meteorologist, U. S. Weather Bureau
DECEIVED
MM 17 %jf
F ‘RGvui- A;:v ;tH T
cmm serial reHSss
GOVERNMENT PRINTING OFFICE
WASHINGTON
1928
Advance Sheets, No. 7
Issued, November, 1928
UNITED STATES DEPARTMENT OF AGRICULTURE
BUREAU OF AGRICULTURAL ECONOMICS
NILS A. OLSEN, CHIEF
ATLAS
OF
AMERICAN AGRICULTURE
Prepared under the Supervision of 0 . E. BAKER, Senior Agricultural Economist
PART II
CLIMATE
SECTION B
TEMPERATURE, SUNSHINE, AND WIND
Contribution from the U. S. Weather Bureau, CHARLES F. MARVIN, Chief
BY
JOSEPH B. KINCER
Senior Meteorologist. U. S. Weather Bureau
RECEIV
m i7 op
PROCUREMENT SECTION
CURRENT SERIAL RECORDS
UNITED STATES
GOVERNMENT PRINTING OFFICE
WASHINGTON
UNITED STATES DEPARTMENT OF AGRICULTURE
WEATHER BUREAU
Charles F. Marvin, Chief
LOCATION OF
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IDENTIFICATION MAP
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KeyWest
ATLAS OF AMERICAN AGRICULTURE
TEMPERATURE
125
123
103
107
105
lOl
ion
97
Figure a / «
° FVrat Order Weather Bureau Stations
* Cooperative Weather Bureau Stations
n Regular Wealher Bureau Stations and Agric. Colleges
* Cooperative Weather Bureau Stations and Agric. Colleges
A Capitals, Regular Weather Bureau Stations
a. Capitals, Reg. Weather Bureau Sta. and Agric. Colleges
* Capitals, Cooperative Weather Bureau Stations
PREPARED BY
JOSEPH BURTON K1NCE;R
METEOROLOGIST U. S. WEATHER BUREAU
FRANCIS J. MARSCHNER
Cartographer Bureau of agricultural Economics
1923
Scale 1:8,000,000
Kilometers
100 200 20(1
Statute Miles
100
109
107
105
99 Longitude Vest 97 of Greenwich. 95
103
■ . - -r - ---relative density in different sections of the country of the Weather Bureau stations. The location of the 200 statinnc
of the Atlas. The number of stations used for each of the several charts is indicated thereon. The more important mountain ranges and river valleys are aUo shown on thfs mfn h ^ (daily / e ' egra P hlc sta T° ns) 13 shown by ® h °' exe cisel^ imoortant Ir T Stat '° nS ! S shoW " by 3 re jf dot Tem P erature observations are not made at all of the stations shown, but 2,300 well-distributed temperature records were used in compiling data for this sectic
M s “re aiso snown on this map by means of hachuring. These physiographic features exercise an important influence in,determining temperature conditions
Figure A.—This map shows the location and
4
TEMPERATURE
Abbot, C. G., and Fowle, F. E.: Volcanoes and Cli¬
mate, Smithsonian Misc. Coll., vol. 60, pp. 24.
Washington, 1913.
Baker, 0. E., and Stine, 0. C.: Climate of the Cotton
Belt. Mo. Weather Rev., vol. 47, pp. 487-9. 1919.
Batchelor, L. D., and West, F. I.: Variation in Mini¬
mum Temperatures Due to the Topography of a
Mountain Valley in Relation to Fruit Growing.
Utah Agr. Exp. Sta. Bull. 141. 1915.
Bigelow, Frank Hagar: The Daily Normal Tempera¬
ture and the Daily Normal Precipitation of the
United States. U. S. Weather Bur. Bull. R, 186
pp., tables. 1908.
- Report on the Temperatures and Vapor
Tensions of the United States Reduced to a
Homogenous System of 24 Hourly Observations
for the 33-Year Interval, 1873-1905. U. S.
Weather Bur., Bull. S, 302 pp., inch tables and
charts. Washington, 1909.
Blair, W. R.: Slope and Valley Air Temperatures.
Mo. Weather Rev., vol. 44, p. 677. 1916.
Blair, T. A.: Some Temperature Correlations in the
United States. Mo. Weather Rev., vol. 45, p. 444.
1917.
Bliss, George S.: Forecasting Minimum Tempera¬
tures for the Cranberry Bogs of New Jersey.
Mo. Weather Rev., vol. 50, pp. 529-33. 1922.
Bouyoucos, George: Soil Temperature. Mich. Agr.
Exp. Sta. Bull. no. 26. 1916.
- Degree of Temperature to Which Soils
May be Cooled Without Freezing. Jour, of Agr.
Res., vol. 20, no. 4, pp. 267-9. 1920.
Bradford, F. C. : The Relation of Temperature to
Blossoming in the Apple and the Peach. Mo.
Agr. Exp. Sta. Res. Bull. no. 53. 1922.
Brooks, Charles F.: The “Old-Fashioned” Winter
of 1917-18. Geographic Review, vol. 5, no. 5. 1918.
Burnham, G. H.: The Weather Element in Rail¬
roading. Mo. Weather Rev., vol. 50, pp. 1-7.
1922.
Coville, F. V.: The Influence of Cold in Stimulat¬
ing the Growth of Plants. Jour, of Agr. Res.,
vol. 20, no. 2, pp. 151-60. 1920.
Cox, H. J.: Thermal Belts and Fruit-Growing in
North Carolina. Mo. Weather Rev. Suppl. 19,
charts, illustrations. 1922.
- Differences Between the Readings of
Sheltered and Unsheltered Thermometers in
Field Work. Mo. Weather Rev., vol. 48, pp.
711-12. 1920.
Day, Preston C.: The Cold Spring of 1917. Mo.
Weather Rev., vol. 45, pp. 285-9. 1917.
- The Cold Winter of 1917-18. Mo. Weather
Rev., vol. 46, pp. 57-80. 1918.
Fawcett, EL S.: Relation of Temperature to Growth
and Infection in the Citrus Scab Fungus (Clad-
osporium Citri). Jour, of Agr. Res., vol. 21, no. 4,
p. 243. 1921.
Fowle, F. E.: (See Abbot and Fowle.)
Gladwin, F. E.: Winter Injury to Grapes. N. Y.
Agr. Exp. Sta. Bull. 433. 1917.
Gordon, James H. : Temperature Survey of the
Salt River Valley, Arizona. Mo. Weather Rev.,
vol. 49, pp. 271-4. 1921.
Haines, E. H.: Influence of Varying Soil Condi¬
tions on Night Air Temperatures. Mo. Weather
Rev., vol, 50, pp. 363-6. 1922.
Hallenbeck, Cleve.: Night Temperature Studies in
the Roswell Fruit District. Mo. Weather Rev.,
vol. 46, pp. 364-73. 1918.
Henry, A. J. : Climatology of the United States.
U. S. Weather Bur., Bulletin Q, 1012 p. 1906.
-Sunspots and Terrestrial Temperature in
the United States. Mo. Weather Rev., vol. 51,
pp. 243-9. 1923.
Hopkins, A. D.: Periodical Events and Natural Law
as Guides to Agricultural Research and Prac¬
tice. Mo. Weather Rev. Suppl. 9. 1918.
-Bioclimatic Zones Determined by Meteoro¬
logical Data. Mo. Weather Rev., vol. 49, pp. 299-
300. 1921.
Humphreys, W. J. : Physics of the Air. The Franklin
Inst., Phila. 1920.
- Factors of Climatic Control. Jour. Frank¬
lin Inst., Phila., Dec. 1919-Jan. 1920. (See also Mo.
Weather Rev., vol. 48, pp. 535-7, 1920, for review by
Ellsworth Huntington.)
Hutt, W. N. : Thermal Belts from the Horticultural.
Viewpoint. Mo. Weather Rev. Suppl. 19. 1922.
Keen, B. A., and Russel, E. J. : Factors Determining
Soil Temperature. Jour, of Agr. Sci., vol. 11, part
3, 1921. Rothamsted, England.
Kincer, Joseph B. : Relation Between Vegetative
and Frostless Periods. Mq v Weather Rev., vol.
47, pp. 106-10. 1919.
-Temperature Influence on Planting and
Harvest Dates. Mo. Weather Rev., vol. 47, pp.
312-23. 1919.
Livingston, Burton E., and Shreve, Forrest: The Dis¬
tribution of Vegetation in the United States
as Related to Climatic Conditions. Carnegie
Inst., Washington, 1921.
Marvin, Charles F.: Solar Radiation Intensities and
Terrestrial Weather. Mo. Weather Rev., vol. 51,
pp. 186-8. 1923.
McAdie, Alexander: Mean Temperatures and Their
Corrections in the United States. At head of
title: United States of America, War Department,
x, 45 pp., tables. 1891.
McGinty, R. A. : Horticulture at High Altitudes.
Colo. Agr. Exp. Sta. Bull. no. 256. 1920.
SELECTED REFERENCES
Miller, Edwin C., and Saunders, A. R. : Some Observa¬
tions on the Temperature of the Leaves of
Crop Plants. Jour, of Agr. Res., vol. 26, no. 1.
1923.
Palmer, A. H. : Death Valley, California, the Hot¬
test Known Region. Mo. Weather Rev., vol. 50,
pp. 10-13. 1922.
Reeder, George: Ground Temperatures Compared
with Air Temperatures in a Shelter. Mo.
Weather Rev., vol. 48, pp. 637-9. 1920.
Russel, E. J. (See Keen and Russel.)
Salmon, S. C. : The Relation of Winter Tempera¬
ture to the Distribution of Winter and Spring
Grains in the United States. Jour, of Amer. Soc.
of Agron., vol. 9, no. 1. 1917.
Saunders, A. R. (See Miller and Saunders.)
Schott, Charles A. : Tables, Distribution, and Va¬
riations of the, Atmospheric Temperature in
the United States and Some Adjacent Parts of
America, xvi, 345 pp. tables, charts., Smithsonian
contributions to knowledge, 277. Washington, 1876.
Seeley, D. A.: Relation between Temperature and
Crops. Mo. Weather Rev., vol. 45, pp. 354-9.
1917.
Shreve, Forrest. (See Livingston and Shreve.)
Sinclair, John G. : Temperatures of the Soil and
Air in a Desert. Mo. Weather Rev., vol. 50,
pp. 142-4. 1922.
Smith, J. Warren: Phenological Dates and Meteor¬
ological Data recorded by Thomas Mikesell at
Wauseon, Ohio. Mo. Weather Rev. Suppl. 2.
1915.
Smith J. Warren, and others: Predicting Minimum
Temperatures from Hygrometric Data. Mo.
Weather Rev. Suppl. 16. 1920.
Stockman, William B.: Temperature and Relative
Humidity Data. U. S. Weather Bur., Bull. O,
29 pp., 2 charts. 1905.
Summers, John N.: Effect of Low Temperature on
the Hatching of Gypsy Moth Eggs. U. S. Dept,
of Agr. Bull. 1080. 1922.
Taylor, George F. (See Wright and Taylor.)
Thiessen, Alfred H. : Story of the Thermometer and
Its Uses in Agriculture. Yearbook, Dept, of
Agri., pp. 157-66. 1914.
Tottingham, W. R.: Temperature Effects in Plant
Metabolism. Jour, of Agr. Res., vol. 25, no. 1.
1923.
U. S. Patent Office: Results of Meteorological
Observations Made under the Direction of the
United States Patent Office and the Smithson¬
ian Institution from the year 1854 to 1859,
INCLUSIVE, BEING A REPORT OF THE COMMISSIONER
of Patents Made at the First Session of the
Thirty-sixth Congress. 2 vol. (36th Cong., 1st
sess., House Ex. doc. 55.) 1861-64.
U. S. Signal Office: Charts Showing Maximum and
Minimum Temperatures by Decades, for All
Years. Cover, title, 37 charts. Washington, 1891.
- Normal Temperature Charts by Decades
for the United States and the Dominion of
Canada. Cover, title, 72 charts. At head of title:
United States of America, War Department. Wash¬
ington, 1891.
U. S. Surgeon General’s Office : Meteorological Regis¬
ter for the Years 1822, 1823, 1824, and 1825,
from Observations Made by the Surgeons of
the Army, at the Military Posts of the United
States. 63 pp. fold. map. Washington, 1826.
- Meteorological Register for the years
1826, 1827, 1828, 1829, and 1830. 161 pp. fold,
map. Philadelphia, New Orleans, 1840.
-- Meteorological Register for Twelve
Years, from 1831 to 1842, Inclusive. 324 pp.
Washington, 1851.
- Army Meteorological Register, for Twelve
Years, from 1843 to 1854, Inclusive, xi, 763,
3 pp., 10 charts. Washington, 1855.
- Statistical Report on the Sickness and
Mortality in the Army of the United States,
Compiled from Records of the Surgeon General’s
Office; Embracing a Period of Sixteen Years,
from January, 1839, to January, 1855, by Richard
H. Coolidge. 703 pp. tables, fold. map. (34th
Cong., 1st sess., Senate Ex. doc. no. 96.) 1856.
U. S. Weather Bureau: Report of the Chief of the
Weather Bureau, 1896-97. 431pp. plates, illus.
tables. (Normal Variability of Temperature.)
Table 5. pp. 284-5. 1897.
- Summaries of Climatological Data by Sec¬
tions. Prepared by the Climatological Division.
2 vol. maps, charts, tables. (U. S. Weather
Bur., Bull. W.) 1912.
- Temperature Departures, Monthly and
Annual, in the United States, January, 1873,
to June, 1909, Inclusive. Bull. U, 584 charts.
1911.
-Temperature Gradients in Latitude, Longi¬
tude, and Altitude. Report of the Chief of the
Weather Bureau, 1900-1901, vol. 2, chap. 4, pp.
361-419. charts, tables. 1902.
-Temperature statistics in extenso for the various
parts of the United States are available in the
following:
- State Weather Services. Reports. ( See
Fassig. Statistics of State Weather Services.)
W. B. no 81. Washington, 1896.
-Monthly Reports of the Climate and Crop
Service. (Climatological Service.) 1896 to June,
1909, and 1914 to date.
-Monthly Weather Review, July, 1909-1913.
-Climatological Data for the United States
by Sections. (Monthly with annual summary.)
Ward, Eobert DeC. : Some Characteristics of United
States Temperature. Mo. Weather Rev., vol. 49,
pp. 595-608, 20 charts following p. 610. 1921.
- Bibliographic Notes on the Temperature
Charts of the United States. Mo. Weather
Rev., vol. 49, pp. 277-280. 1921.
_Hot Waves, Hot Winds, and Chinook Winds
in the United States. Sci. Monthly, vol. 17, no. 2,
pp. 146-67. 1923.
_ Cold Waves, Northers, and Blizzards in
the United States. Sci. Monthly, vol. 16, no. 5,
pp. 440-70. 1923.
West, F. L. (See Batchelor and West.)
Woolard, E. W.: Historical Note on Charts of the
Distribution of Temperature, Pressure, and
Winds over the Surface of the Earth. Mo.
Weather Rev., vol. 48, pp. 408-11. 1920.
Wright, R. C., and Taylor, George F.: The Freezing
Temperatures of Some Fruits, Vegetables, and
Cut Flowers. U. S. Dept, of Agr. Bui. 1133. 1923.
Young, Floyd D.: Effect of Topography on Tem¬
perature Distribution in Southern California.
The Calif. Citrograph, vol. 5, no. 7. 1920.
- Influence of Exposure on Temperature
Observations. Mo. Weather Rev., vol. 48, pp.
709-11. 1920.
-Nocturnal Temperature Inversions in
Oregon and California. Mo. Weather Rev.,
vol. 49, pp. 138-48. 14 figs, tables. 1921.
- Notes on the January, 1922, Freeze in
Southern California. Mo. Weather Rev., vol. 51,
pp. 581-85. 1923.
- Substituting Fruit Temperatures for Air
Temperatures in Regulating Orchard Heating
for Oranges. Mo. Weather Rev., vol. 52, pp.
381-87. 1924.
SUNSHINE
Allard, H. A. (See Gamer and Allard.)
Garner, W. W., and Allard, H. A. : Effect of the Rela¬
tive Length of Day and Night and Other Factors
of the Environment on Growth and Reproduction
in Plants. Jour, of Agr. Res. March, 1920.
Hand, Irving F. (See Kimball and Hand.)
Hearn, George D.: Relation of Sunlight to Plant
Development. Mo. Weather Rev., vol. 50, p. 423.
1922.
Kimball, H. H.: Duration and Intensity of Twilight.
Mo. Weather Rev., vol. 44, pp. 614-26. 1916.
Kimball, H. H., and Hand, Irving F. : Daylight Illu¬
mination on Horizontal, Vertical, and Sloping
Surfaces. Mo. Weather Rev., vol. 20, pp. 615-28.
1922.
Kincer, Joseph B.: Sunshine in the United States.
Mo. Weather Rev., vol. 48, pp. 12-17. 1920.
Palmer, Andrew H. : The Agricultural Significance
of Sunshine as Illustrated in California. Mo.
Weather Rev., vol. 48, pp. 151-54. 1920.
Seeley, Dewey A.: The Heating of Plants in Sun¬
light as a Factor in Growth. Mo. Weather Rev.
vol. 47, pp. 327-28. 1919.
Stewart, J. B. : Effect of Shading on Soil Conditions.
U. S. Bur. of Soils Bui. no. 39. 1907.
Ward, Robert DeC.: Bibliographic Note on Sun¬
shine in the United States. Mo. Weather Rev.,
vol. 47, pp. 794-5. 1-919.
WIND
Beck, Anne Louise: The Earth’s Atmosphere as a
Circular Vortex. Mo. Weather Rev., vol. 50, pp.
393-401. 1922.
Bowie, Edward H., and Weightman, R, Hanson: Types
of Storms in the United States and Their Aver¬
age Movement. Mo. Weather Rev. Suppl. 1. 1914.
-Types of Anticyclones in the United States
and Their Average Movement. Mo. Weather
Rev. Suppl. 4. 1917.
Day, Preston C. : The Winds of the United States
and Their Economic Uses. U. S. Dept. Agr. Year¬
book, 1911, pp. 337-50.
Fuller, P. E.: The Use of Windmills in Irrigation in
the Semi-arid West. Farmers’ Bui. 866, U. S.
Dept. Agr. 1917.
Gregg, Willis R. : An Aerological Survey of the
United States. (Results of Observations by
Means of Kites.) Mo. Weather Rev., vol. 50, pp.
229 h12. 1920.
Gregg, Willis R., and Van Zant, J. Parker: The Wind
Factor in Flight. (Analysis of One Year’s
Record of the Air Mail.) Mo. Weather Rev., vol.
51, pp. 111-25. 1920.
Marvin, Charles F. : Air Drainage Explained. (With
Reference to Temperature Influence.) Mo.
Weather Rev., vol. 42, pp. 583-85. 1914.
-The Law of the Geoidal Slope and Fallacies
in Dynamic Meteorology. Mo. Weather Rev., vol.
48, pp. 565-82. 1920.
Mitchell, Charles L.: West Indian Hurricanes and
Other Tropical Cyclones of the North Atlantic
Ocean. Mo. Weather Rev. Suppl. 24. 1924.
Samuels, I. T. : Correlations Between Wind Ve¬
locities at the Surface and Those in the Free
Air. Mo. Weather Rev., vol. 50, pp. 83-89. 1922.
Van Zant, J. Parker. (See Gregg and Van Zant.)
Wieghtman, R. Hanson. (See Bowie and Weightman.)
5
TEMPERATURE
|emperature is one of the most important factors
that make up the climate of a region. Plant and
animal life is constantly under the influence of the
temperature of the air near the earth’s surface, and it
is with this temperature that we are mostly concerned
as regards agricultural enterprises and our bodily com¬
fort. For climatological purposes the measure of tem¬
perature is obtained from thermometers freely exposed
to the air near the surface of the earth and shielded
from the direct rays of the sun, but in such a manner as
not materially to obstruct the atmospheric circulation.
Source of data. —The records made by cooperative
observers of the Weather Bureau have been largely used
in preparing the charts and graphs here presented.
These stations are in most cases located in the open
country and small towns, where the instruments are
more or less free from the artificial influences that fre¬
quently affect the temperature records made at the first
order Weather Bureau stations in the larger cities. The
records are made by standard maximum and minimum
thermometers, exposed in approved shelters, usually at
an elevation of 5 feet above the ground surface. The
stations are inspected from time to time by trained offi¬
cials of the Weather Bureau, with a view to having the
instrumental exposure and observational work in
general as uniform as possible throughout the
country. The records in most cases cover a period
of at least 20 years, although some for shorter
periods were used, particularly in the far Western
States, where fewer long records are available. 1
SOLAR AND PHYSICAL CLIMATE
with clear, dry air, the earth’s surface heats very rapidly
under direct insolation, and high day temperatures
result. At night radiation of heat is rapid from the
barren ground, as the dry atmosphere offers little obstruc¬
tion to the passage of heat into space, and a rapid
decrease in temperature results. Although the diurnal
range in temperature in deserts is much greater than in
other types of climate, the high day temperatures are
not so oppressive as the readings of the thermometer
would appear to indicate, owing to the extreme dryness
of the atmosphere. During the heated hours of the day
the difference in the indications of two thermometers,
one having the bulb covered with freely evaporating
water and the other uncovered, is very great. This dif¬
ference is known in meteorology as the “depression of
the wet-bulb temperature. ” Its magnitude gives some
indication of the degree of physical discomfort experi¬
enced during the prevalence of high temperatures which,
in general, varies inversely with the depression of the
wet-bulb temperature. At Yuma, Ariz., the average
daily maximum dry-bulb temperature for the month of
July is about 106° F. and the wet-bulb temperature is
75° F., the average depression of the wet-bulb ther¬
mometer at the time of maximum temperature being
ANNUAL MARCH OF TEMPERATURE
SELECTED STATIONS.
The climate that would prevail if the earth had
a homogeneous land surface and if there were no
atmosphere is termed “solar climate.” Under such
conditions the amount of insolation received at any
place would depend wholly on the declination of
the sun, and all places of the same latitude would
have similar temperature conditions. “Physical
climate,” or that actually prevailing, is a modifica¬
tion of “solar climate,” produced by the presence
of the atmosphere, the unequal distribution of land
and water surfaces, differences in altitude, air
movement, direction of ocean currents, and other
causes. There are three major types of physical cli¬
mate—marine, continental, and mountain. There
are also several minor types, principal among
which are those designated as “coast or littoral cli¬
mate” and “desert climate.”
Marine climate.- —The marine type of climate is
characterized by comparatively uniform tempera¬
tures throughout the year, and by small diurnal
range in temperatures. Water surfaces under the
influence of the sun’s rays warm more slowly than
land surfaces and cool more slowly in the absence
of direct insolation. The temperature of the over-
lying air likewise changes slowly, and this results
in a more uniform temperature condition than is
found in other types of climate. The progress of
the seasons is also retarded, winter lingering later
into spring and summer into fall. Marine climates
have, therefore, comparatively pleasant summer^,
mild winters, cool springs, and warm autumns.
Continental climate. —The continental type of
climate is characterized by greater temperature
extremes and more rapid changes in temperature.
The coldest month in northern latitudes is usually
January and the warmest is July, the time of maxi¬
mum and minimum temperatures occurring earlier
than in f 3 marine type. The diurnal and annual
ranges, as well as the irregular changes in tempera¬
ture from day to day are large, and increase, as a
rule, with increasing distance from the oceans. In the
United States practically all districts east of the Rocky
Mountains have this type of climate, even near the
Atlantic coast, as the general atmospheric drift is off¬
shore, which prevents the marine influence from being
effective to any considerable distance inland. The
annual march in temperature is shown for selected
stations in Figures 1 and 72, and the diurnal in Figures 85
and 86. The characteristic increase both in the annual
and diurnal temperature range with increasing distance
inland may be noted in these figures.
Extreme types of continental climate are found in
deserts. Here in the absence of vegetal covering, and
i The maps and graphs contained in this section of the Atlas were originally completed
and ready for publication in 1917, but owing to the exigencies brought about by the
World War publication could not be accomplished at that time. The original data
embrace the 20-year period from 1895 to 1914, inclusive, corresponding to that covered
by Section I, “Frost and the Growing Season,” and by Section B, “Precipitation and
Humidity,” of this Atlas, both of which have already been published.
Since 1914 eight years of additional records have become available. These have been
carefully examined and compared with the original data to determine what changes,
if any, would be necessary, in order that the several maps and graphs should portray
general conditions up to and including the year 1922.
The following maps have been fully revised to satisfy this requirement: Figures 3
6, 15, 16, 20, 25, 26, 30, 31, 36, 40, 41, 45,-46, 50, 51, 55, 56, 60, 61, 65, 66, 70, and 71. The
graphs which were intended only to show certain characteristic variations in tempera¬
ture in different portions of the country, such as Figure 4, were not revised. It was
found that all other maps and graphs required practically no changes to represent
conditions virtually up to the time of publication.
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K
ever, this condition is confined to a narrow belt along
the immediate coast, especially as regards cool summers,
since mountain barriers prevent the extension of the
marine influence to any considerable distance inland.
The marine character of climate obtaining on the Pacific
coast is shown by the graphs for San Francisco and
North Head in Figures 1 and 85. In these graphs
the small annual and diurnal temperature ranges may
be noted. They show also the temperature ranges along
the Atlantic coast, where the characteristics of the
continental type predominate, although the marine influ¬
ence is appreciable as compared with the central section
of the country. Figure 1 also visualizes the temperature
gradient from north to south in the United States for
the several seasons of the year, separately for the Atlan¬
tic coast, the Mississippi Valley, the Rocky Mountain
region, and the Pacific Coast States.
i Mountain climate. —Mountain climate, as compared
with that of the adjacent lowland, is characterized by
lower temperatures throughout the year, but the diur¬
nal and other variations are generally somewhat less than
those experienced at lower elevations. The average
decrease in temperature with increase in altitude in the
free air is about 1° F. for each 330 feet, but the rate
varies with the season of the year and is also much
affected by local conditions. It is more rapid in
summer than in winter and is greatest during the
warmer hours of the day. Temperature inversions,
which frequently occur during the colder months
and especially at night, sometimes give to moun¬
tain slopes a higher temperature than is experienced
in the near-by lower valleys. This condition is
brought about by the air in contact with the moun¬
tain sides through the influence of surface radiation
in the absence of direct insolation becoming colder
than the free air over the valley and the increased
weight, resulting from cooling and contraction, sets
up a convectional circulation, or interchange of air
between that near the surface of the colder moun¬
tain side and the warmer free air above the valley
below. This circulation is continuous as long as
the difference in air density is maintained. In
such cases there is a mudh larger diurnal tempera¬
ture range in the valley than on the mountain sides.
Under direct insolation surface soil temperatures
in high altitudes become relatively higher than the
adjacent air temperatures because the rarefied con¬
dition of the atmosphere and the comparatively
small amount of aqueous vapor contained in it offer
little obstruction to the passage of the sun’s rays.
These conditions, however, have a reverse effect at
night by affording less resistance to radiation, and
consequently there is a greater diurnal range in soil
temperature on mountains than on lowlands.
DEG.
Figure 1.—This graph shows the annual march of temperature at selected stations,
arranged in four belts, each extending north and south. It visualizes the monthly
changes in temperature for different sections of the country and also the latitudinal
gradient for the several seasons. East of the Rocky Mountains the decrease in winter
temperature from south to north is large, especially in the Mississippi Valley, whereas
in summer the decrease is moderate. The small seasonal changes in temperature
characteristic of marine climates and the great seasonal differences in temperature typi¬
cal of continental climates are graphically contrasted in the belts marked “Pacific coast 1
and “Mississippi Valley region ”
IMPORTANT TEMPERATURE DATA
For the presentation of the climatic factors of
any place the most important temperature data
required are as follows: Average daily temperature;
average daily range and average daily variability;
average monthly temperature; average monthly
range and absolute monthly extremes; seasonal
temperature, especially the average summer (June,
July, and August) and average winter (December,
January, and February) temperature; average
annual temperature and average annual range; and
the frequency of occurrence and duration of certain
significant temperatures.
Average daily temperature. —The true average
daily temperature corresponds closely to the aver¬
age of 24 hourly observations, but as several other
combinations of hourly values give averages that
about 31° F., whereas at Chicago the averages for the
same period are about 80° and 69°, respectively, the av¬
erage depression of the wet-bulb temperature being only
11°. So far as bodily comfort is concerned the high
temperature at Yuma is greatly mitigated by the in¬
creased opportunity for evaporation. Over large areas
in the Southwest this desert climate prevails, though not
in such degree as at Yuma. The large diurnal temper¬
ature range in desert regions is shown in the section
marked “Arid Plateau” in Figure 85 and also by the
thermograph trace sheet for Yuma, Ariz., in Figure 87.
In some cases coasts of large bodies of water have
climates closely allied to the continental type and in
others the marine characteristics dominate, depending
on the surface drift of the atmosphere, whether from
the land or the water. When this drift is on-shore
the coast has a marine climate, as along the immediate
Pacific coast of the United States. When the drift
is off shore, a more^or less modified form of continental
type of climate obtains, which is exemplified along the
Atlantic coast of the United States. On the Pacific
coast the summers are cool, owing to the prevailing
westerly winds, and the winters are mild for the same
reason, while extremes in temperature are rare. How-
differ but little from the true daily average some one of
these is generally used to reduce observational work.
The combination
(7 a. m. + 2 p. m.+ 9 p. m. + 9 p. m.)
4
gives a value which differs only slightly from the true
daily average, and
(sunrise+ 2 p. m. + 9 p. m.)
3
also gives fairly accurate results. The formula
(maximum + minimum)
2
is easy of application and very satisfactory when depend¬
able maximum and minimum thermometers are used
and properly exposed. The mean of the daily extremes
is, as a rule, slightly too high, but it usually does not vary
more than one-half of a degree from the true daily aver¬
age. This combination is employed by the Weather
Bureau to obtain the average daily temperature, and the
data for the accompanying charts and diagrams were
compiled by its use.
Daily •range and daily variability of temperature. —The
normal diurnal march of temperature may be described
6
7
ATLAS OF AMERICAN AGRICULTURE
TEMPERATURE
UNITED STATES DEPARTMENT OF AGRICULTURE
WEATHER BUREAU, Charles F. Marvin, Chief
AVERAGE SUMMER TEMPERATURE, JUNE-AUGUST, INCLUSIVE
Based on the Records of about 2,300 Stations, mostly 20 Years or more in Length and Determined
/ i FR0M THE Means of the Daily Extremes i 1
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HanilibaL
ihattan
Coinnlbi'i
^'rrwJVL-
Jefferson CityJ*
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71,1 V
Nashville
?? Stillwater
BOSTON
Imith
Musko^w
-Amarillo
Corinth
Colombia
Athens
ARBUCKLE
/ o AtV.u'U'
Augusta
, Roswell
DEGREES FAHRENHEIT
'alias'
ffickson
aso
Midland
HIGHEST TEMPERATURE EVER OBSERVE
Figure 3
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V \ > -T
Ives tO}
Orlando
p 5 Galveston
wiscoi
Matagorda,
Figure 4
Ink^jL
\QT<ec-hoVe
ANNUAL MAXIMUM TEMPERATURES EACH YEAR 1895-1914
Jupiter
STATIONS
EASTPORT, ME.
BUFFALO, N. Y.
SEATTLE. WASH.
SAN FRANCISCO, CAL.
; Mianu
DENVER, COLO.
SCALE OF SHADES
NORFOLK, VA.
COLUMBUS. OHIO
UNDER 90
90 TO 95
95 TO 100
100 TO 105
105 TO 110
110 TO 115
115 TO 120
A30VE 120
Brownsville
SALT LAKE CITY. UTAH.
MONTGOMERY. ALA.
floridcLBo^
PALESTINE, TEX.
TOPEKA, KANS.
EL PASO. TEX.
KeyWest
MILES CITY. MONT.
FRESNO, CAL
YUMA. ARIZ.
101
103
105
\29
Figure 2
107
125
123
inn
° First Order Weather Bureau Stations
* Cooperative Weather Bureau Stations
n Regular Weather Bureau Stations and Agric. Colleges
* Cooperative Weatker Bureau Stations and Agric. Colleges
Capitals, Regular Weather Bureau Stations
0 Capitals, Reg. Weather Bureau Sta. and Agric. Colleges
* Capitals, Cooperative Weather Bureau Stations
PREPARED BY
JOSEPH BURTON KINCER
METEOROLOGIST U. S. WEATHER BUREAU
FRANCIS J. MARSCHNER
CARTOGRAPHER BUREAU OF AGRICULTURAL ECONOMICS
1923
Scale 1:8,000,000
Kilometers
200 300
Based on the records
of about 600 stations
Statute Miles
100
i."
100
109
107
105
99 Longitude West 97 of Greenwich 95
in.;
Figure 2. This map shows the average summer temperature, June to August, inclusive. East of the semiarid Great Plains the crops grown and the types of farming are determined largely by the temperature of the summer season. In this area there are six more or less distinct agricultural regions, occupying in a general way east and west belts. (1) The Subtropical Crops Belt, extending along the coast of the Gulf of Mexico and up the Atlantic coast as far as
Charleston, S. C. In this region the characteristic crops are citrus fruits, winter vegetables, sugar cane, and rice, and the average summer temperature, is 80° to 82° F. (2) The Cotton Belt, lying immediately to the northward, which has an average summer temperature decreasing from about 81° at the southern boundary to 77° at the northern. In this region cotton and corn are the dominant crops, constituting about three-fourths of the acreage of all crops. (3) To
the northward of the Cotton Belt lies the Corn and Winter Wheat Belt, having an average summer temperature decreasing from 77° along the southern border to about 75° in the northern portion west of the Appalachian Mountains and 70° east of the mountains. In this region corn, wheat, tobacco, and hay are the most important crops, and diverse types of agriculture prevail. (4) The Corn Belt, which lies west of the Appalachian Mountains, and has a summer
temperature of about 75 ^along the southern border and 69° along its northern border. Winter wheat supplements the corn crop in its southern portion and spring oats in its northern portion. Hay, mostly timothy and clover in the east and alfalfa in the west, is also an important crop. (5) The Spring Wheat Region, comprising western Minnesota, the Dakotas, and eastern Montana. The average summer temperature in this region decreases from about 69° at the
southern boundary to 63 near the Canadian border, and 59 along its northern margin in Canada. Spring wheat, oats, barley, flax, and hay are the important crops. (6) The Hay and Pasture Region comprising the northern border States from Minnesota eastward and extending southward along the Appalachians. This region, in which hay and pasture constitute over 50 per cent of the improved land, has an average summer temperature ranging from about 59° to
70° With reference to temperature conditions the Spring Wheat Region is only a subhumid grass land extention of the originally forested Hay and Pasture Region lying to the east, while the Corn Belt is really a large and extraordinarily fertile portion of the Corn and Winter Wheat Belt
Figure 3 shows the highest temperatures ever observed, based on the records of the regular reporting and of selected cooperative stations up to and including the year 1922. Temperatures over 100° F have been experienced in all portions of the country, except in the higher altitudes of the Rocky Mountain and Appalachian areas, the central and northern portions of both the Pacific and Atlantic coasts, portions of New England, and in the Florida Peninsula
Figure 4 shows for selected stations the maximum temperature for each of the 20 years from 1895 to 1914, inclusive. Each dot represents the highest temperature recorded for an individual year, there being 20 dots for each station
8
ATLAS OF AMERICAN AGRICULTURE
Figure 5.—This map shows the average winter temperature, December to February, inclusive. East of the Rocky Mountains the average winter temperature increases from near zero in northwestern Minnesota and
northeastern North Dakota to about 32° F. in central New Jersey, southern Ohio, and the central portions of Missouri and Kansas, and to about 55° along the Gulf coast. To the westward it ranges from somewhat less
than 15° at the higher altitudes of the Rocky Mountain region to about 55° in the lower Colorado River Valley and along the coast of southern California. The Subtropical Crops Belt has an average winter temperature
ranging from about 50° in the rice district of Louisiana to 70° in extreme southern Florida. In the Cotton Belt it ranges from 40° to 50°, and even 55° in southern Texas; in the Corn and Winter Wheat Belt from about
30° along the northern border of the belt to about 40° in the southern; in the Corn Belt from 15° in southwestern Minnesota to about 30° along the southern margin, and in the Spring Wheat Eelt it varies from near
zero to about 15°. In the Hay and Pasture province the average winter temperature varies widely. It is about zero in northeastern Minnesota and reaches 35° locally in the central Appalachian valleys
briefly as follows: In continental climates the daily
minimum usually occurs about the time of sunrise, and
in marine climates somewhat earlier. Beginning at this
time there is a gradual increase until the maximum is
reached, usually from two to four hours after noon in the
continental type of climate and about noon, or shortly
after, in the marine type. From the time of the maxi¬
mum there is a gradual decrease until the next morning
when the minimum is again reached. Figure 85 shows
for selected stations, representing the
Atlantic and Gulf coasts, the Mississippi
Valley, the Rocky Mountain region, the
Arid Plateau, and the Pacific coast, the
diurnal march of temperature for the
months of January, April, July, and
October. This graph shows the charac¬
teristic features of the normal daily tem¬
perature curve for the principal climatic
divisions of the United States. The signi¬
ficance of the average daily temperature
for a locality depends on the amplitude of
the periodic daily range and also on the
nature of the nonperiodic or accidental
changes that occur from day to day, or the
daily variability. For example, the aver¬
age daily temperature for August at San
Diego, Calif., and at Bismarck, N. Dak., is
about 68° F., but at Bismarck the average
daily maximum is 81° as compared with
73° for San Diego, whereas the average
daily minimum is 55° at Bismarck and 62°
at San Diego. Thus while the average tem¬
perature at the two places for this month
is the same, Bismarck has an average daily
range of 26° and San Diego only 11°, which
makes a marked difference in the actual
temperature experienced. Again, the aver¬
age temperature for a given month may be the same at
two different places, and one may be subject to large
daily variability, as shown by the difference between
the mean temperatures for successive days, and the other
may have comparatively uniform temperatures from day
to day. Under such conditions, although the average
monthly temperatures would be similar, the temperature
conditions actually experienced would be wholly different.
The daily variability of temperature is least in the marine
type of climate and greatest in the continental type,
increasing, as a rule, toward the center of continents.
It is also greater in winter than in summer, owing to
the more pronounced cyclonic and anticyclonic action
during the winter. Figure 72 shows for each month of
the year the average daily temperature range for selected
stations in different sections of the United States, and
the auxiliary charts accompanying the average monthly
temperature charts show the average daily maximum
and average daily minimum temperatures each month.
Figures 81-84 show the average daily range in tempera¬
ture throughout the United States for the months of
January, April, July, and October; and Figure 86 shows
for selected stations, representing the principal types
of climate found in this country, the maximum and min¬
imum temperatures each day for the years 1913 and
1914. In this graph the tops of the vertical bars show
the daily maxima and the bottoms of the bars the daily
minima. The length of the bars indicates the ampli¬
tude of the daily range, and their centers show the daily
mean values. The relative position of the bars for suc¬
cessive days indicates the daily variability. This graph
shows the characteristics of important temperature
data for different sections of the country and for the
several seasons of the year in such manner as to facili¬
tate comparison of conditions in different localities.
Average monthly temperature and monthly extremes .—The
average of the daily temperatures of a month
is known as the average monthly tempera¬
ture, and ife significance depends on the
extent of the periodic variations in the
daily values, from which it is derived,
and on the frequency and amount of the
nonperiodic or accidental fluctuations that
are liable to occur from time to time dur¬
ing the month. Figures 12, 17, 22, 27, 32,
37, 42, 47, 52, 57, 62, and 67 show the
average temperatures for each month of the
year, based on the records of about 1,200
stations, which in most cases cover a period
of at least 20 years. Accompanying these
are auxiliary charts showing for each month
the average daily maximum and the average
daily minimum temperatures, and others
showing the highest and the lowest mean
monthly temperature observed during the
28-year period 1895 to 1922, inclusive.
In addition to the average of the daily
maxima and the average of the daily mini¬
ma it is important to know the average of
the monthly extremes, that is, the average
of the highest temperatures and the aver¬
age of the lowest temperatures recorded
each month, for a long series of years, and
the absolute maximum and absolute mini¬
mum for each month. These data are shown for a con¬
siderable number of representative stations by the large
graph-chart (fig. 72). These graphs show for the sta¬
tions named, and for each month of the year, (1) the
average monthly temperatures, (2) the average of the
daily maxima and of the daily minima, (3) the average
of the monthly maxima and of the monthly minima,
and (4) the absolute maximum and absolute minimum.
Figure 6.—This map shows the lowest temperatures ever observed up to and including the year 19:
based on the records of the regular reporting and of selected cooperative stations. These absolute minimi
temperatures range from —65° F. in eastern Montana to 41° at Key West. Fla. Temperatures of —40° hs
been recorded in northern New England and northern New York, and as low as —20° as far south
Tennessee, Arkansas, and Oklahoma, and zero temperatures have occurred in the central Gulf coast d
tricts. Along the central and southern California coast the lowest temperatures of record are from 24° to S
9
TEMPERATURE
UNITED STATES DEPARTMENT OF AGRICULTURE
WEATHER BUREAU, CHARLES F. MARVIN, CHIEF
AVERAGE ANNUAL MINIMUM TEMPERATURE
WISCON^
c ar 6 1,tN ^
i ARKANSAS
Scale 1:17,100,000
Kilometers
IOO 200 300 400 SOO gOO 700 800 SOQ lOOO
Statute Miles
200 300
Based on the records
of about 600 stations
Figure 7.—This map shows the average of the lowest temperatures recorded each winter. As a rule, the lowest temperatures in the United States occur in the northern portions of North Dakota and Minnesota,
usually about -40° F. or slightly lower. The other extreme is found at Key West, Fla., where the lowest temperature for the year ordinarily does not go below 50°. Along the immediate Gulf coast the average annual
minimum is 22° to 25°, whereas along the immediate Pacific coast it ranges from about 25° at the north to 36° at the south. The marine influence is markedly shown by the north and south trend of the isotherms along
the Pacific coast, and is noticeable along the Atlantic coast, where the isothermal lines trend in a northeasterly direction as they approach the ocean and terminate at the coast several hundred miles farther north than
the^ latitude at which they cross the Mississippi Valley. The tempering effect of the Great Lakes is shown by the trend of the isotherms along their leeward shores in Michigan, Ohio, and New York
120
15
105
100
Figure 7
SCALE OF SHADES
DEGREES FAHRENHEIT
BELOW -40
-40 TO -30
-30 TO -20
-20 TO -10
-10 TO 0
0 TO 10
10 TO 20
20 TO 30
OVER 30
PREPARED BY
JOSEPH BURTON KINCER
M ETEOROLOGIST
FRANCIS J MARSCHNER
CARTOGRAPHER
120
105
100
Figures 8 and 9 show the number of years in the 20-year period, 1895-1914, that the minimum temperature was 6° or more, and 9° F. or more, respectively, below the average annual minimum. These maps show
the frequency of significant negative departures from the average annual minimum temperature. (Fig. 7)
Figure 10 shows the average annual number of days with temperature continuously below freezing during the day. In the northern portions of Minnesota and North Dakota there are, on the average, more than 100
days each year when the temperature does not rise above 32° F., but southward there is a rapid decrease to less than 1 day along the Gulf coast. Along the Pacific coast, except at the extreme north, the average is also
less than 1 day
Figure 11 shows the average annual number of days with minimum temperature at freezing, or lower. In portions of the northern Plains States and in the northern Rocky Mountain districts freezing temperatures
usually occur on 180 to 200 days of the year, and in northern New York and northern New England on 165 days or more. To the southward there is a rapid decrease in number to about 5 days along the Gulf coast,
whereas along the southern Pacific coast the average is less than 1 day annually
10
ATLAS OF AMERICAN AGRICULTURE
Figure 12.-—January is, as a rule, the coldest month of the year. The lowest temperatures usually occur in the northern portion of Minnesota and North Dakota, where the average temperature for the month is
near zero. The temperature gradient from north to south is much more rapid in winter than in summer, the average January temperature increasing to about 55° F. at the coast of the Gulf of Mexico, an increase on
the average of 1° for each 25 miles. In July the average increase in temperature from North Dakota to the Gulf coast is 1° for each 90 miles. (See fig. 42.) Throughout the interior of the continent temperature
changes during January are frequent and often abrupt. Very cold weather is sometimes experienced in the northern interior districts in this month, temperatures as low as —40° to —50° being recorded occasionally
in northern Minnesota, North Dakota, and eastern Montana, and records of —25° to —35° have been made in northern New York and New England. Along the Gulf coast the lowest recorded temperatures for this
month range from 11° to 15°. Freezing temperatures are of infrequent occurrence in southern Florida and also along the coast of southern California
Figures 13 and 14 show for January the average daily maximum and the average daily minimum temperatures. In northern North Dakota the average daily temperature range in January is about 25° F (see fig 81)
the average daily maximum being somewhat less than 20° and the average daily minimum —5° to —10°. To the southward there is a rather uniform increase in both these values, the average maximum reaching 60°
to 70° and the minimum 40° to 50° along the Gulf coast. From the Rocky Mountains westward the average daily maximum for this month varies from 25° and 30° in the central and northern Rocky Mountain
districts to about 65° along the southern California coast, and the minimum varies from nearly —10° in the central Rocky Mountain districts to about 45° along the coast of central and southern California
Figures 15 and 16 show the highest and the lowest mean January temperatures that occurred in the 28-year period 1895-1922. The variation in these temperatures is large in most districts, particularly in the north-
central border States, where the mean January temperature one year may be as much as 20° or 25° F. warmer than in another year. Along the Pacific coast this variation is less than 10°
11
TEMPERATURE
UNITED STATES DEPARTMENT OF AGRICULTURE
WEATHER BUREAU. Charles F. Marvin, Chief
AVERAGE FEBRUARY TEMPERATURE
MI SS.OU
Scale 1:17,100,000
Kilometers
lOO 200 300 ,.400 500 600 700 800 SOO lOOO
Statute Miles
200_300
Based on the records of about 1,200 stations, mostly
20 years or more in length, and determined from
the means of the daily extremes
125 <$0 120
115
110
105
oo
Figure 17
SCALE OF SHADES
DEGREES FAHRENHEIT
0 TO 10
10 TO 20
20 TO 30
30 10 40
40 TO 50
50 TO 60
60 TO 70
05
120
100
Figure 17. The average temperature in February does not differ materially from that of January, but as a rule February is slightly the warmer month. The lowest average temperature for this month, about 5° F.
is found in the northern portions of Minnesota and North Dakota. Along the Canadian border to the eastward it is about 10° higher. To the southward there is a progressive increase to about 55° along the Gulf coast.
Cold waves continue to be of comparatively frequent occurrence in February, usually entering the United States from the Canadian Northwest and sometimes overspreading practically all the country east of the Rocky
Mountains. In fact, the coldest weather of the year frequently occurs during the early part of this month. Temperatures as low as —25° have occurred in February as far south as Kansas and Missouri and records
as low as 0 have been made in the central Gulf coast. However, there is usually an appreciable increase in temperature in the latter part of February, freezing weather, as a rule, not occurring along the immediate Gulf
coast after the 20th of the month
Figures 18 and 19 show for February the average^daily maximum and the average daily minimum temperatures. East of the Rocky Mountains the average daily maximum for this month ranges from about 15° F.
on the Canadian border in Minnesota and North Dakota to about 65° along the Gulf coast, increasing to 75° at Key West, Fla. In the West the average daily maximum varies from about 30° in the central Rocky
Mountain districts to nearly 75° in the lower Colorado River Valley. The average daily minimum east of the Rockies ranges from -10° at the Canadian boundary in the Red River Valley to 45° or 50° along the Gulf
coast. In the West the average minimum varies from about -5° in the central Rocky Mountain districts to about 45° along the central and southern coast of California and in the lower Colorado River Valley
Figures 20 and 21 show the highest and the lowest mean February temperatures in the 28-year period 1895-1922. These mean temperatures do not differ materially, except in the more northern districts, from
those for January
12
ATLAS OF AMERICAN AGRICULTURE
UNITED STATES DEPARTMENT OF AGRICULTURE
WEATHER BUREAU, Charles F. Marvin, Chief
AVERAGE MARCH TEMPERATURE
OKTAJIOM^
j ARKANSAS
Scale 1:17,100,000
Kilometers
100 200 300 400 5 00 600 1 1
800 900 lOO O
Statute Miles
200 300
Based on the records of about 1,200 stations, mostly
20 years or more in length, and determined from
the means of the daily extremes
Figure 22.—With the advent of spring there is a rather rapid increase in temperature in most sections of the country. In the northern interior region March is about 15° F. warmer than February, but the increase
in temperature from February to March becomes less marked with progress southward, being only about half as great along the Gulf coast as along the northern border of the country. The lowest average temperature
for March, about 20°, is found along the northern border in North Dakota and Minnesota, and there is an increase southward to about 60° or 65° along the Gulf coast. In the more northern States extremely cold
weather occurs occasionally in this month, from —35° to —40° having been recorded in North Dakota and Montana. But the March cold waves usually lose intensity rapidly in their southward and eastward progress,
"["emperatures below zero have never been recorded in this month south of the fortieth parallel of latitude, except in the Texas Panhandle, Kansas, and a few localities to the eastward. As a rule freezing weather is not
experienced in the Gulf States, except in the extreme northern portions, after March 15
Figure 22
10 TO 20
20 TO 30
30 TO 40
40 TO 50
50 TO 60
60 TO 70
70 TO 80
.V* 80
HIGHEST MONTHLY MEAN TEMPERATURE
aL/ i „ MARCH i \, f/
Figure 25
AVERAGE DAILY MAXIMUM TEMPERATURE
tv- --.MARCH , \ 1 V
Figure 23
wiscol
wiscoi
ARRAN.
jARKAN.
SCALE OF SHADES
SCALE OF SHADES.
Based on the records
of about 200 first
order Weather Bureau
stations
Based on the records
of about 600 stations
AVERAGE DAILY MINIMUM TEMPERATURE
“=W„'o , MARCH. i \ j
Figure 24
jARKAN.
SCALE OF SHADES
Based on the records
of about 600 stations
LOWEST MONTHLY MEAN TEMPERATURE
»sL 0 / | , MARCH. i \ 1
wiscoi
new/
jARKAN.
SCALE OF SHADES
Based on the records
of about 200 first
order Weather Bureau
stations
Figures 23 and 24 show for March the average daily maximum and the average daily minimum temperatures. In the northern border States east of the Rocky Mountains the average daily maximum is about 35° F.,
but this increases southward to about 70° along the Gulf coast and to 80° in portions of the Florida Peninsula and in the lower Rio Grande Valley. In the West the average March maximum varies from somewhat less
than 40° in the central and northern Rocky Mountain districts to 80° in the lower Colorado River Valley. The average daily minimum east of the Rockies increases from 10° along the northern border in North Dakota
and Minnesota to somewhat more than 50° along the Gulf coast, and to 68° at Key West, Fla. In the West it ranges from about 5° in portions of the Rocky Mountain districts to 50° at San Diego, Calif., and in the
lower Colorado River Valley
Figures 25 and 26 show the highest and the lowest mean March temperatures occurring in the 28-year period 1895-1922. The range of variation in the mean temperature for March is much larger than for February,
especially in the northern interior States, where the month in one year may be 30° F. warmer than in another year
13
TEMPERATURE
UNITED STATES DEPARTMENT OF AGRICULTURE
WEATHER BUREAU. CHARLES F. Marvin. CHIEF
AVERAGE APRIL TEMPERATURE
.MINNESOTA!
■LA.I1 O MTV
ARKANSAS
Scale E17,100,000
Kilometers
lOO 290 300 400 soo 600 700 800 900 IOOO
Statute Miles
200 300
Based on the records of about 1,200 stations, mostly
20 years or more in length, and determined from
the means of the daily extremes
7bJ£
*S<0 120
10
105
100
Figure 27
SCALE OF SHADES
DEGREES FAHRENHEIT
20 TO 30
30 TO 40
40 TO 50
50 TO 60
60 TO 70
70 TO 80
PREPARED BY
JOSEPH BURTON KINCER
METEOROLOGIST
FRANCIS J. MARSCHNER
CARTOGRAPHER
105
120
100
Figure 27.—As spring advances the increase in temperature becomes more pronounced, the average for April in North Dakota and northern Minnesota being nearly 20° F. higher than for March. Southward the
increase in temperature becomes progressively less rapid, amounting to about 6° along the Gulf coast. The average temperature for April ranges from about 40° along the Canadian boundary to nearly 70° at the Gulf of
Mexico. Along the Pacific coast April is only slightly warmer than March, but in the Interior Plateau and Rocky Mountain districts the increase in temperature during April is rapid. Cold periods occur occasionally
during April, the lowest temperature recorded in this month at a regular reporting station of the Weather Bureau located in eastern Montana being —10°. Freezing temperatures have been experienced early in ApriI as far
south as Mobile, Ala., but as a rule such temperatures do not occur after the 15th of this month south of a line extending through central Virginia, western North Carolina, and southern Kentucky westward to central
Missouri and Kansas
Figures 28 and 29 show for April the average daily maximum and the average daily minimum temperatures. In the principal agricultural districts east of the Rocky Mountains the usual daily temperature range in
April varies from about 15° to 27° F., but to the westward, except in the Pacific Coast States, it is considerably larger. (See fig. 82.) East of the Rocky Mountains the average daily maximum for this month ranges
from about 45° in northern Maine and the extreme upper Lake region to nearly 80° along the Gulf coast, and the average daily minimum from somewhat less than 30° in the extreme north to about 60° at the Gulf. From
the Rocky Mountains westward the average daily maximum varies from somewhat less than 50° at the higher altitudes in the Rocky Mountain region to nearly 90° in southwestern Arizona, and the minimum from about
20° in portions of Colorado and Wyoming to 50° along the coast of southern California and in the lower Colorado River Valley
Figures 30 and 31 show the highest and the lowest mean April temperatures in the 28-year period 1895-1922.
but is still large in the northern border States
The variation in the mean temperature for April in different years is considerably less than for March,
14
Figure 32. May throughout most of the United States is usually characterized by the prevalence of mild temperatures. East of the Rocky Mountains the average May temperature ranges from about 50° F. along the
northern border of the country to 75° at the Gulf of Mexico, being 5° to 15° higher than for April. Along the immediate Pacific coast it ranges from 50° at the north to 60° at the south. In the lower Rio Grande and
Colorado River Valleys the average May temperature is slightly over 80°. The lowest temperature of record in May at a regular reporting station is 6? in northern North Dakota. Freezing temperature has occurred in
this month as far south as northern Texas, but east of the Mississippi River freezing weather has never been known south of the Ohio River and southern Pennsylvania, except in elevated districts. As a rule freezing
temperatures do not occur after May 10 south of South Dakota, the central portions of Iowa and Wisconsin, and the lower Lakes. High temperatures sometimes occur in May, especially in the Great Valley of California
and in the lower Colorado River Valley, 110° having been recorded at Red Bluff and Fresno, Calif., and 120° at Yuma, Ariz.
-—"_oo
LOWEST MONTHLY MEAN TEMPERATURE
wiscoi
hsroisj
jARKAN.
S CALE O F SHADES
_ 30° TO 40° -
' . : 7 40° TO 50°
50° TO 60°
_ 60° TO 70°
ZZZj 70 ° to 80 °
Based on the records
of about 200 first
order Weather Bureau
stations
Figures 33 and 34 show for May the average daily maximum and the average daily minimum temperatures. East of the Rocky Mountains the average daily maximum increases from ahn„t fin° f • .u ' ' “T
region and along the eastern Maine coast to 85° in the southern section of the Cotton Belt, but along the immediate Gulf coast it is only about 80° In the West the average dal I v ? th ® UPP6r L
about 60 at the higher altitudes in the Rocky Mountain States and also along the north Pacific coast to 95° in the lower Colorado River Valley. The average daily minimum for Mav east of^^R^M V 3 "' 68 f '
from about 40 along the northern border of the country to about 70° along the immediate Gulf coast, and in the West from less than 30° in the central Rocky Mountain districts to 60° in the^ r'l T"S"* T
. F, S ures 35 and 36 show the highest and the lowest mean May temperatures in the 28-year period 1895-1922. The lowest mean temperature for May experienced during this 28 vear niuod C ° ? ^ *' Ver Yf e
in the upper Lake region and in some of the Rocky Mountain districts to 73° along the Gulf coast 7 P S th 28 ' year period ranges from about 40°
115
15
UNITED STATES DEPARTMENT OF AGRICULTURE
WEATHER BUREAU, CHARLES F. MARVIN, CHIEF
AVERAGE JUNE TEMPERATURE
MINNESOTA!
wise
MISSOURI
•AROl*^ T 5
iarkan^sas
PREPARED BY
JOSEPH BURTON KINCER
METEOROLOGIST
Scale 1:17,100,000
Kilometers
FRANCIS J. MARSCHNER
CARTOGRAPHER
1°° 200 300 400 500 600 700 800 900 lOQQ
Statute Miles
200 300
Based on the records of about 1,200 stations, mostly
20 years or more in length, and determined from
the means of the daily extremes
Figure 37.—In June the average temperature along the Canadian border east of the Rocky Mountains is about 60° F., or approximately 10° higher than in May. To the southward there is a rather pronounced increase
to 70° in central Iowa and Ohio, and thence a less rapid rise to about 80° in the Gulf coast section. At the lower elevations in the West the average June temperature is mostly between 60° and 70°, but in some of the
southern districts it is much higher, reaching 90° in the lower Colorado River Valley. Along the immediate Pacific coast it ranges from 55° at the north to 65° at the south. High temperatures occur occasionally during
June, the highest of record at a regular reporting station of the Weather Bureau being 117° at Yuma, Ariz. Temperatures of 106° to 110° have been experienced in June in the Great Plains States, and 100° or higher has occurred
quite generally throughout the country, except in the Northeastern States, in the Great Lakes region, in the higher altitudes of the Rocky and Appalachian Mountain districts, and along the central and north Pacific coast
TEMPERATURE
110
105
100
Figure 37
SCALE OF SHADES
DEGREES FAHRENHEIT
40 TO 50
50 TO 60
60 TO 70
70 TO 80
80 TO 90
90 TO 100
120
105
100
Figure 40
HIGHEST MONTHLY' MEAN TEMPERATURE
MbJL / * „ JUNE I \ 1
WISCOT
hsroisj
M1SSJ3URJ
jARKAN*
SCALE OF SHADES
Based on the records
of about 200 first
order Weather Bureau
stations
Figures 38 and 39 show for June the average daily maximum and the average daily minimum temperatures. East of the Rocky Mountains the average daily maximum for June ranges from about 70° F., in the upper
Lake region and on the north Atlantic coast to about 90° in the southern portion of the Cotton Belt, increasing to nearly 100° in the lower Rio Grande Valley. In the West the average daily maximum ranges from 60° along
the north Pacific coast and less than 70° in the central and northern Rocky Mountain districts to about 105° in the lower Colorado River Valley. The average daily minimum temperature ranges from less than 40° in
the central and northern Rocky Mountain districts and 50° along the northern border of the country to about 75° along the immediate Gulf coast
Figures 40 and 41 show the highest and lowest mean June temperatures in the 28-year period 1895-1922. Variation in the mean temperature for June during this period is not pronounced in any section of the country.
In the principal agricultural districts it is generally about 10° F. and along the Pacific coast is only 5°
16
ATLAS OF AMERICAN AGRICULTURE
UNITED STATES DEPARTMENT OF AGRICULTURE,
WEATHER BUREAU, CHARLES F. MARVIN, CHIEF
AVERAGE JULY TEMPERATURE
Figure 42
MINNESOTA]
SS.OURJ
i ARKAN »>S A S
OTTO! A
Scale 1:17,100,000
Kilometers
lOO _200_ 300 400 500 600 700 800 300 lO OO
Statute Miles
200 300
600
Based on the records of about 1,200 stations, mostly
20 years or more in length, and determined from
the means of the daily extremes
125
SCALE OF SHADES
DEGREES FAHRENHEIT
50 TO 60
60 TO 70
70 TO 80
80 TO 90
90 TO 100
PREPARED BY
JOSEPH BURTON KINCER
METEOROLOGIST
FRANCIS J. MARSCHNER
CARTOGRAPHER
100
105
Figure 42.—July is usually the warmest month of the year, except along the Pacific coast, where the marine type of climate prevails. East of the Rocky Mountains the average July temperature ranges from between
55° and 70° F. in the northern border States to about 82° on the Gulf coast. Along the Pacific coast it increases from about 55° at the north to 67° at the south. The highest July temperature usually occurs in south¬
western Arizona and southeastern California, where the average for the month varies from 90° to 98°. In July periods of hot weather are comparatively frequent in the interior sections of the country. In some of the
important agricultural districts, particularly in the Middle West, the heated periods are occasionally accompanied by hot winds which are injurious to vegetation. July temperatures of from 105° to 110° have been exper¬
ienced in nearly all localities between the Rocky Mountains and the Mississippi River and at many points to the eastward. However, along the central and north Pacific coast in the higher altitudes of the Rocky and
Appalachian Mountains and likewise at points along the north Atlantic coast and in the Florida Peninsula the highest temperatures ever recorded are less than 100°
Figures 43 and 44 show for July the average daily maximum and the average daily minimum temperatures. The average daily maximum east of the Rocky Mountains ranges from between 70° and 80° F. along the
Canadian Border to about 100° in the lower Rio Grande Valley, and in the far West from about 60° along the north Pacific coast to nearly 110° in the lower Colorado River Valley. The average daily minimum ranges
from less than 40° in the higher Rocky Mountain districts and about 50° in northern North Dakota to 75° along the Gulf coast and in the lower Colorado River Valley. The average daily range in temperature in July in the
Eastern States is mostly from 20° to 25°, except along the coasts of the Great Lakes and Atlantic Ocean, and in the Western States is from 25° to 45°, except along the immediate Pacific coast. (See fig. 83.) This is 5°
to 10° greater than in January
Figures 45 and 46 show the highest and the lowest mean July temperatures in the 28-year period 1895-1922. Variations in the mean July temperature from year to year are, as a rule, not pronounced, the extreme
range being in most districts from 5° to 7° F., as compared with 10° to 20° for January
*17
TEMPERATURE
UNITED STATES DEPARTMENT OF AGRICULTURE
WEATHER BUREAU, CHARLES F. MARVIN. CHIEF
Figure 47
AVERAGE AUGUST TEMPERATURE
WISCO
s.oura
Scale 1:17,100,000
Kilometers
lOO 200 3 00_400 500 600 700 800 _ 900 lOO O
FRANCIS J. MARSCI
CARTOGRAPHER
Statute Miles
200 300
Based on the records of about 1,200 stations, mostly
20 years or more in length, and determined from
the means of the daily extremes
600
. ■
105
Hid
50 TO 60
60 TO 70
70 TO 80
80 TO 90
90 TO 100
PREPARED BY
JOSEPH BUFfON KINCER
METEOROLOGIST
105
100
115
120
Figure 47.—During August temperature conditions do not, as a rule, differ materially from those in July, but August is usually slightly cooler, except along the Pacific coast. At some points on the Pacific cpast
September is even warmer than August. East of the Rocky Mountains the coolest August weather usually occurs in northern Michigan and in the highlands of New. York and New England, where the average temper¬
ature for the month ranges from 60° to 65° F. The temperature gradient from north to south is much smaller in summer than in winter. In July and August the difference between the average temperature along the Canadian
boundary and that on the Gulf coast is about 15°, but in midwinter it is about 50°. Along the immediate Pacific coast the characteristic cool summer weather usually continues during August, but in the Great Valley of
California and in southwestern Arizona hot weather often prevails, the average temperature in the lower Colorado River Valley reaching 95°. Temperatures as high as 116° have been experienced in August in the lower
Colorado River Valley, 113° at points in the Great Valley of California and eastern Washington, 112° in northeastern Texas, and 110° locally in the northern Great Plains region
AVERAGE DAILY MAXIMUfvr'TEMPERATURE:
AUGUST | \ i
Figure 48
wisco
SCALE OF SHADES
Based on the records
of about 600 stations
HIGHEST MONTHLY MEAN TEMPERATURE
-J I — „„ AUGUST , \ | \
Figure 50
wiscot
NEW/
SCALE OF SHADES
Based on the records
of about 200 first
order Weather Bureau
stations
AVERAGE DAILY MINIMUM TEMPERATURE
mmL , AUGUST . \ |
Figure 49
rpTOlS'
SCALE OF SHADES
Based on the records
of about 600 stations
LOWEST MONTHLY MEAN TEMPERATURE'
ateJ , , AUGUST -i I
Figure 51
wiscqI
newj
jARKAN.
SCALE OF SHADES
Based on the records
of about 200 first
order Weather Bureau
stations
Figures 48 and 49 show for August the average daily maximum and average daily minimum temperatures. Along the immediate Pacific coast the daily maximum temperature during this month is low, ranging from
60°' F. at the north to 74° at the south. In the southern portion of the Great Valley of California the average daily maximum temperature is near 100°, and in the lower Colorado River Valley it reaches 108°. East of the
Rocky Mountains the average daily maximum temperature ranges from about 72° in northern Michigan and 70° on the eastern Maine coast to 100° in the lower Rio Grande Valley. The average daily minimum for August
ranges from about 35° in the higher altitudes of the middle and northern Rocky Mountain districts to about 75° along the Gulf coast and in the lower Colorado River Valley. In practically all the important agricultural
sections of the United States it is over 50°
Figures 50 and 51 show the highest and the lowest mean August temperatures in the 28-year period 1895-1922. The range in variation in this mean August temperature does not differ materially from that for July,
being mostly about 5° and less than 10° F. throughout practically the entire United States
18
ATLAS OF AMERICAN AGRICULTURE
UNITED STATES DEPARTMENT OF AGRICULTURE
WEATHER BUREAU, CHARLES F. MARVIN, CHIEF
,'MlNNF/sOTAj
S.0HK1
rt>ya
FRANCIS J. MARSCHNER
CARTOGRAPHER
Scale 1:17,100,000
Kilometers
200 300 400 5QQ 600
800 SOO lOO O
Statute Miles
200 300
Based on the records of about 1,200 stations, mostly
20 years or more in length, and determined from
the means of the daily extremes
600
Figure 52.—The average September temperature east ot the Rocky Mountains ranges from about 55° F. along the Canadian boundary, where it is about 8° lower than in August, to about 78° along the Gulf coast,
where it is 2 or, 3 lower. At the lower-dlevations of the Rocky Mountain and interior Plateau regions the average September temperature varies mostly from 50° to 65°, but in the Great Valley of California it is 70° to 75°
and in the lower Colorado River Valley 80° to 85°. In some localities along the immediate Pacific coast September is usually the warmest month in the year. High temperatures are experienced occasionally in September,
especially between the Rocky Mountains and the Mississippi River, where records of 100° or higher are quite general. Likewise, in the interior valleys of California, high temperatures sometimes occur in this month, the
highest being 110 in the southern Portion of the Great Valley. Cool weather may also occur in September, freezing temperatures having been recorded as far south as the Ohio River and the southern portions of Kansas
and Missouri; but east of the Rocky Mountains frost does not usually occur in September south of the northern border States
I25<
55 120
LI 5
no
105
Figure 52
SCALE OF SHADES
DEGREES FAHRENHEIT
40 TO 50
50 TO 60
60 TO 70
70 TO 80
80 TO 90
120
[05
1O0
Figure
AVERAGE DAILY MINIMUM TEMPERATURE
I SEPTEMBER , \ ] \
tNOJJL
K^L AJ1 O MjV>
jARKAN.
SCALE OF SHADES
Based on the records
of about 600 stations
Figure 56
LOWEST MONTHLY MEAN TEMPERATURE
i , SEPTEMBER , \ f
^WISCONSIN;
SCALE OF SHADES
___ 40° TO 50°
_I 50° TO 60°
_ 60° TO 70°
__ 70° TO 80°
80° TO 90°
Based on the records
of about 200 first
order Weather Bureau
stations
Figures 53 and 54 show for September the average daily maximum and the average daily minimum temperatures. East of the Rocky Mountains the average daily maximum for c T.. "TT
the extreme northern portion of Michigan and on the eastern Maine coast to about 88° along the Gulf coast and 95° in the lower Rio Grande Valley. West of the Rockies it varies from Ibou 60^7 7 i p
coast to somewhat more than 100° in the lower Colorado River Valley. The average daily minimum east of the Rockies ranges from about 40° in the extreme northern portions of North D k ^fiwi 6 7^ ^7
70 along the Gulf coast and ,n the West it varies from less than 30° in the higher altitudes of the central and northern Rocky Mountain region to nearly 70° in the lower Colorado River Valley ^
Figures 55 and 56 show the highest and the lowest mean September temperatures in the 28-year period 1895-1922. The range of variation in mean September temperatures is somewhatl™ t a * . ■
mostly between 8° and 15° F. in the principal agricultural areas ^ ewhat larger than for August, bei
19
Figure 57
UNITED STATES DEPARTMENT OF AGRICULTURE
WEATHER BUREAU, CHARLES F. MARVIN, CHIEF
AVERAGE OCTOBER TEMPERATURE
wisco
M I S S.OURJ
SLA*H OMS
;arkan»sAs
Scale 1:17,100,000
Kilometers
200 3QO 400 500 600 700 800 900 lOO O
Statute Miles
200 300
Based on the records of about 1,200 stations, mostly
20 years or more in length, and determined from
the means of the daily extremes
TEMPERATURE
1,0 F RgU ;; f 7 iT? U R n \ OC M 0ber + there + u S a pr0n0UnCed decrea f 'n temperature, except in southern Florida and along the Pacific coast. The decrease below the average September temperature is in general from 10° t(
5 F. East of the Rocky Mountains the average temperature for October ranges from about 45° along the northern border of the country to 70° on the Gulf coast. In the Rocky Mountain and Interior Plateau regions a
‘°K I T X 20 ” hi!ter in ,a 'l eyS NewM “ i “' California. Alo„ s fh. imm edia,e Pacific coast the „ia s e teotp^lj inc^ses^
the north to 60 at the south. Temperatures below zero have been experienced at a few points in the North Central States in October, the lowest of record at a regular station of the Weather Bureau beina -16° ir
Carolina ^-tana. Freezing temperatures have occurred in this month nearly to the Gulf coast. In a normal year freeing weather occurs before the last of October as farsouth asthe of Lui
Said the nuZr'dectars rapfd^ 85 ' 5 '"’' 11 “ “ ‘ , ° rt,0nS ““““ a " d ° klahoma - Alons ,he Ca " a<lia " b ” d « r temperatures occur, on the a,era S e, „„ about 15 days in October, but to the south.
Figure 58
AVERAGE DAILY MAXIMUM TEMPERATURE^
OCTOBER
WISCOT
UTOlSj
jARKAN,
SCALE OF SHADES
Based on the records
of about 600 stations
Figure 60
HIGHEST MONTHLY MEAN TEMPERATURE
SajL , , OCTOBER , \ i
NVISCOI
jARKlVN*
SCALE OF SHADES
40° TO 50°
'■'I - 50° TO 60°
60° TO 70°
_ 70° TO 80°
80 ^ TO 90°
Based on the records
of about 200 first
order Weather Bureau
stations
Figures 58 and 59 show for October the average daily maximum and the average daily minimum temperatures. East of the Rocky Mountains the average daily maximum ranges from about 55° F. in the northern
portions of New England, Michigan, Wisconsin, and Minnesota to nearly 90° in the lower Rio Grande Valley, and in most districts is about 10° lower than for September. In the West it varies from about 55° in the
central and northern Rocky Mountain districts to 90° in the lower Colorado River Valley. The average daily minimum ranges from about 20° in the higher altitudes of the Rocky Mountain region to about 60° along the
central Gulf coast. In the Corn Belt the average of the daily minima for October ranges from about 40° in the northern portion to 50° in the southern
Figures 60 and 61 show the highest and the lowest mean October temperatures in the 28-year period 1895-1922. In the interior districts the range of variation in mean October temperatures during the 28-year
period is mostly from 10° to 15°, but near the Atlantic, Gulf, and Pacific coasts it is smaller
20
UNITED STATES DEPARTMENT OF AGRICULTURE
WEATHER BUREAU, CHARLES F. MARVIN, CHIEF
AVERAGE NOVEMBER TEMPERATURE
INNEfeOTi
WISCO
341S01S
MI SS.OUR]
O K V L A.H Q/M Af
j ARKANSAS
PREPARED BY
JOSEPH BURTON KINCER
METEOROLOGIST
Scale 1:17,100,000
Kilometers
300 JiOO SOO 600 700 800 SOO IOOO
CARTOGRAPHEI
Statute Miles
200 300
Based on the records of about 1,200 stations, mostly
20 years or more in length, and determined from
the means of the daily extremes
300
ATLAS OF AMERICAN AGRICULTURE
Figure 62.—During November the decrease in temperature, as a rule, is rapid, the average temperature for' the month being usually from 10° to 20° F. lower than that for October, except along the Gulf and Pacific
coasts. The greatest decrease in temperature is in Minnesota and the Dakotas. East of the Rocky Mountains the average November temperature ranges from about 25° in northern Minnesota and North Dakota to about
60° along the Gulf coast, and 70° in southern Florida. Along the Pacific coast it increases from 45° at the north to about 60° at the south. In November cold waves of considerable severity sometimes advance from the
Canadian Northwest and overspread the north Central States, but they usually lose force rapidly after entering the United States and are seldom of long duration. Zero temperature has never been experienced ata regular
Weather Bureau station in this month south of the Ohio River, but freezing weather has occurred southward to Tampa, Fla. Freezing temperatures are not ordinarily reached in November, however, along the Texas coast
nor south of Gainesville, Fla. The lowest temperature of record for this month at a regular reporting station is —33° in northern Montana
Figure 62
SCALE OF SHADES
DEGREES FAHRENHEIT
20 TO 30
30 TO 40
40 TO 50
50 TO 60
60 TO 70
70 TO 80
.V* 80
.
100
120
HIGHEST MONTHLY MEAN TEMPERATURE
t NOVEMBER , \ j
Figure 65
AVERAGE DAILY MAXIMUM TEMPERATURE
, , NOVEMBER , \ I
jFlGURE 63
WTSCO!
new/
newj
jARKAN»
SCALE OF SHADES
SCALE OF SHADES
Based on the records
of about 200 first
order Weather Bureau
stations
Based on the records
of about 600 stations
AVERAGE DAILY MINIMUM TEMPERATURE
NOVEMBER , \ J V
Figure 64
-WISCO!
lnoJJL
wew/me
SCALE OF SHADES
Based on the records
of about 600 stations
LOWEST MONTHLY MEAN TEMPERATURE:
| - NOVEMBER i \ I
Figure 66
frjolSj
new /
jARKAN.
SCALE OF SHADES
0° TO 10°
10° TO 20° '
__ 20° TO 30°
_ 30° TO 40°
_ 40° TO 50°
50- TO 60°
60° TO 70°
Based on the records
of about 200 first
order Weather Bureau
stations
Figures 63 and 64 show for November the average daily maximum and the average daily minimum temperatures. East of the Rocky Mountains the average daily maximum ranges from about 35° F. along the north-
central border of the United States to about 70° along the Gulf coast. Except along the Gulf and south Atlantic coasts it is 10° to 20° lower than for October. In the West the average daily maximum varies from less
than 40° in the higher altitudes of the Rocky Mountain region to 80° in the lower Colorado River Valley. The average daily minimum for November ranges from about 10° in northern North Dakota, northeastern Montana,
and in the higher altitudes of Colorado and Wyoming to about 50° along the central Gulf and southern California coasts, and nearly 70° in southern Florida
Figures 65 and 66 show the highest and the lowest mean November temperatures in the 28-year period 1895-1922. East of the Rocky Mountains the variation from year to year in mean November temperatures is large,
particularly in the North Central States, where the range is as great as 30° F. or more. The coldest November on record occurred in North Dakota and eastern Montana in 1896, when the mean temperature for the month
was about 7°
21
TEMPERATURE
UNITED STATES DEPARTMENT OF AGRICULTURE
WEATHER BUREAU, CHARLES F. Marvin, Chief
AVERAGE DECEMBER TEMPERATURE
-—_ \ 1 r 7 l—
i Ml,SSL)IsR!
C,AR? U /
j AIT KAN.
Scale 1:17,100,000
Kilometers
300 400 500 600 700 800 SOO lOOQ
FRANCIS J. MARSCHNER
CARTOGRAPHER
Based on the records of about 1,200 stations,
20 years or more in length, and determine
the means of the daily extremes
Statute Miles
200 300
120
105
10O
Figure 67
105
100
?0 80
• . F, S ur « 67 -- Du , rl "g December the temperature, as a rule, continues to decrease rapidly. East of the Rocky Mountains the decrease in the average temperature from November to December ranges from about 15° F
m the northern border States to 7 or 8 along the Gulf coast. The average December temperature ranges from about 10° in northwestern Minnesota and northeastern North Dakota to 55° in the Gulf coast region and 70°
m extreme southern Florida In the valleys of the Rocky Mountain and Interior Plateau regions the average temperature for the month varies from 20° to 35°, except in the Mexican-border States Z e it isVcall v as
high as 55 . Along the Pacific coast the average temperature increases from about 44° at the north to 56° at the south. During December cold waves become more frequent and severe Ind in“ interf”the
country very low temperatures occasionally occur The lowest of record for this month at a regular Weather Bureau station is -50° in northern Montana. Temperatures of -10°'to -15° have been experienced in
December as far south as southern Kansas and Missouri and -5° in portions of Tennessee and North Carolina. Along the central Gulf coast the lowest temperature recorded in December is 14°
Figure 69
AVERAGE DAILY MINIMUM TEMPERATURE
feWlP DECEMBER ^ i \ I
LT4 01SJ
AUKAN.
SCALE OF SHADES
Based on the records
of about 600 stations
Figure 71
LOWEST MONTHLY MEAN TEMPERATURE
Vw too DECEMBER \ }.
jARKAN*
SCALE OF SHADES
1 -10° TO 0°
0° TO 10° _
_• _ 10° TO 20°
20° TO 30°
_ 30° TO 40°
jjjjpi 40° TO 50°
13B8S 50° TO 60°
W' 60° TO 70°
Based on the records
of about 200 first
order Weather Bureau
stations
Figures 68 and 69 show for December the average daily maximum and the average daily minimum temperatures. East of the Rocky Mountains the average daily maximum ranges from about 20° F. in northern
Minnesota and North Dakota to about 65 along the Gulf coast, and 70° in southern Florida and extreme southern Texas. In the West it varies from less than 30° in the centra! Rocky Mountain region to nearly 70° in the
lower Colorado River Valley. The average of the daily minima for December east of the Rockies ranges from about zero in northern Minnesota and North Dakota to 66° at Key West, Fla. In the West it varies from below
zero at the higher altitudes in the Rocky Mountain region to 48° on the coast of southern California, decreasing slowly along the coast northward to 46° at San Francisco and 40° along the Washington coast
Figures 70 and 71 show for December the highest and the lowest mean temperatures in the 28-year period 1895-1922. The variation from year to year is comparatively large in most districts
20° F. in the central and northern Rocky Mountain districts and in the North Central States, about 10° in the Gulf coast region, but only about 5° along the north Pacific coast
The range is 15° to
22
23
ATLAS OF AMERICAN AGRICULTURE
TEMPERATURE
UNITED STATES DEPARTMENT OF AGRICULTURE
WEATHER BUREAU, Charles F. Marvin, Chief
annual march of significant temperatures
^4 602
Hilton
--
\jjjackuiar. y.^ V
hvxiJs\
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Huron
'^iganset
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‘^162 * St *
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an’ktmj
’otns bluff
Mome
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Papers'
jscrva-
p&i River
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SrrwQL.
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^Oca Pk. &
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l a H
35fenvpftf
—
marillo °
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WICHITA
•x MTS.
ARBUCKXE
fesiliaiy
DEGREES
FAHRENHEIT
davis
FortStotikto]
ABILENE TEX.
Houston!
ilvestoi
MOBILE,
Galveston
talaxjorda,
Jupiter
Mianu
tsville
pioridxvSoA
Scale 1:8,000,000
Kilometers
PREPARED BY
JOSEPH BURTON KINCER
METEOROLOGIST
FRANCIS J. MARSCHNER
CARTOGRAPHER
KeyVvest
Statute Miles
mo
9? of Greenwich
Figure 72
107
H;, KEY GRAPH
J FMAMJ JASONDJ
“““ • ■
S
-■
4
j
I
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Figure 72.—The graphs comprising this figure show for selected representative Weather Bureau stations and for each month of the year (1) the average monthly temperature, indicated by the solid, central line in the graph for each station; (2) the average daily maximum and the average daily minimum temperatures, indicated respectively by the upper and the lower dotted lines; (3) the average monthly maximum and minimum temperatures, that is, the average
of the highest and lowest temperatures occurring each month, indicated respectively by the upper and the lower dashed lines; and (4) the absolute monthly maximum and minimum temperatures or the highest and the lowest temperatures ever recorded -in each month, indicated respectively by the extreme upper and lower dot and dash lines. The graphs also show (5) the average daily range in temperature for each month, this being represented by the vertical
distance between the dotted lines showi ng the average of the daily maxima and the average of the dai ly minima; (6) the average monthly range represented by the vertical distances each month between the dashed li nes of average monthly maximum and minimum temperature; (7) the range in absolute monthly temperatures represented by the distances each month between the extreme dot and dash li nes showing absolute maximum and minimum temperatures; and
(8) the distance between the highest point reached by the top line and lowest reached by the bottom line shows the absolute annual range. The graphs are arranged geographically, each being placed directly over the location of the station it represents, the station in most cases being near the center of the graph. These graphs show the annual march of temperature and afford comparisons of important temperature data for the different sections of the country. The
large diurnal monthly, and annual ranges in temperature characteristic of continental climates and the small ranges in temperature typical of marine climates will be noted upon comparing the graphs for the interior sections of the United States with those for the Pacific coast. The smaller annual range in temperature in the southern United States will also be noted upon comparing the graphs for the southern portion with those for the northern portion of the country
24
AVERAGE DATE WHEN MEAN DAILY TEMPERATURE^
, RISES ABOVE 35° . , \Y\ X
"iGURE 73
[cdfr** 1
SCALE OF SHADES
APR. 1 TO APR. 16
MAR. 16 TO APR. 1
MAR. 1 TO MAR. 16
FEB. 16 TO MAR. 1
TEB. 1 TO FEB. 16
JAN. 16 TO FEB. 1
PERMANENTLY
ABOVE 35°
PERMANENTL'
Based on the records
of about 200 first
order Weather Burea^
stations
AVERAGE DATE WHEN MEAN DAILY TEMPERATURE
SULL /, ^ RISES ABOVE 55° . , \T\_-\
Figure 75
mOi§-
WCV '-' 6 \
SCALE OF SHADES
jARKAN*
JUN. 16 TO JUL. 1
JUN. 1 TO JUN. 16
MAY 16 TO JUN. 1
MAY 1 TO MAY 16
APR. 16 TO MAY 1
APR. 1 TO APR. 16
MAR. 16 TO APR. 1
MAR. 1 TO MAR. 16
FEB. 16 TO MAR. 1
FEB. 1 TO FEB. 16
JAN. 16 TO FEB. 1
PERMANENTLY
ABOVE 55°
-|.Y ABOVE 55
IANENTI
ATLAS OF AMERICAN AGRICULTURE
Based on the records
of about 200 first
order Weather Bureau
stations
AVERAGE DATE WHEN MEAN DAILY TEMPERATURE
•W-. May .,^RISES ABOVE 45° i j. \Yi XX
Figure 74
[NOIS.
jARKAN.
SCALE OF SHADES
MAY 1 TO MAY 16
APR. 16 TO MAY 1
APR. 1 TO APR. 16
MAR. 16 TO APR. 1
MAR. 1 TO MAR. 16
FEB. 16 TO MAR. 1
FEB. 1 TO FEB. 16
JAN. 16 TO FEB. 1
PERMANENTLY
ABOVE 45°
lNENTLJ
IRMANENTL}
Based on the records
of about 200 first
order Weather Bureau
stations
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^ y _l
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\ JL T
A Sn o k vr-sH
J D A V ° V f
;e5oTyJ
AVERAGE DATE WHEN MEAN DAILY TEMPERATURE \
[Figure 76
RISES ABOVE 65‘
below
65°
SCALE OF SHADES
-PERMANENTLY
BELOW 65°
Hg JUL. 1 TO JUL. 16
_ JUN. 16 TO JUL. 1
_ JUN. 1 TO JUN. 16
_ MAY 16 TO JUN. 1
_MAY 1 TO MAY 16
_ APR. 16 TO MAY 1
_ APR. 1 TO APR. 16
_ MAR. 16 TO APR. 1
_ MAR. 1 TO MAR. 16
__ FEB. 16 TO MAR. 1
FEB. 1 TO FEB. 16
Y . JAN. 16 TO FEB. 1
~J PERMANENTLY
ABOVE 65°
jARKAN*
apr-'^t
FEB-'Gir^.
i FEB-'^.
PERMANENTLY ABOVE 6'
Based on the records
of about 200 first
order Weather Bureau
stations
—
Figures 73, 74, 75, and 76 show the dates on which the average daily temperature in spring rises above 35°, 45°, 55°, and 65° F., respectively. These charts show the progress of the season as indicated by the
movement northward of significant isotherms. The hardier cereals germinate and begin growth when the average daily temperature reaches about 35°; consequently the seeding of spring wheat begins in the Spring Wheat
Belt about this time, followed by spring oats one or two weeks later. When the average temperature reaches about 45° potato planting begins throughout the Central and Northern States, and when 55° is reached the
planting of corn has begun in the eastern United States. By the time 65° is reached corn planting is practically over in the Corn Belt and alfalfa is almost ready for the first cutting. This line of 65° reaches the eastern
coast of Maine, the extreme upper Lake region, and the central and northern Rocky Mountain districts about July 20 and then immediately begins its retreat southward. I n the regions to the north of or above this extreme
limit of 65°, and along the immediate Pacific coast as far south as Point Conception, where also an average temperature of 65° is not attained during the summer, the crops are practically confined to hay, pasture, small
grain, potatoes, and the hardier fruits and vegetables. In extreme southern Florida the average daily temperature never falls below 65°, and here limes, pineapples, and subtropical fruits are the important crops
AVERAGE DATE WHEN MEAN DAILY TEMPERATURE
igasJ... - , , FALLS BELOW 45° , , \f\ X
Figure 79
wiscoi
hsrolS,
jARKANj
SCALE OF SHADES
IENTLY *B(
NOV. 16 TO DEC. 1
DEC. 1 TO DEC. 16
DEC. 16 TO JAN. 1
JAN. 1 TO JAN. 16
PERMANENTLY
ABOVE 45°
IMANENTL'
Based on the records
of about 200 first
order Weather Bureau
stations
Figure 78 /
SEPT.-16-
AVERAGE DATE WHEN MEAN DAILY TEMPERATURE
, FALLS BELOW 55° , \n X"''
SCALE OF SHADES
_ AUG. 16 TO SEP. 1
’ SEP. 1 TO SEP. 16
|_ SEP. 16 TO OCT. 1
gm OCT. 1 TO OCT. 16
_ OCT. 16 TO NOV. 1
_ NOV. 1 TO NOV. 16
_ NOV. 16 TO DEC. 1
_ DEC. 1 TO DEC. 16
DEC. 16 TO JAN. 1
-•y.:, JAN. 1 TO JAN. 16
: I PERMANENTLY
ABOVE 55°
Based on the records
of about 200 first
order Weather Bureau
stations
’ERMANENTLY ABOVE 55 {
IAM20 C
AVERAGE DATE WHEN MEAN DAILY TEMPERATURE
teaL , , FALLS BELOW 35° . , \Y\ X
Figure 80
WISCOI
\ sW
\ NcAKOL
SCALE OF SHADES
OCT. 16 TO NOV. 1
NOV. 1 TO NOV. 16-
NOV. 16 TO DEC. 1
DEC. 1 TO DEC. 16
DEC. 16 TO JAN. 1
JAN. 1 TO JAN. 16
PERMANENTLY
ABOVE 35°
PERMANEf
Based on the records
of about 200 first
order Weather Bureau
stations
Figures 77, 78, 79, and 80 show the dates on which the average daily temperature in autumn falls below 65°, 55°, 45°, and 35° F., respectively. When the average daily temperature in the fall declines to 65°, the
seeding of winter wheat becomes general throughout practically the entire Winter Wheat Belt; when it falls to 55°, the cutting and shocking of corn is in progress in the northern border States and husking or snapping
from the standing stalk is beginning in the Corn Belt; when it falls to 45°, corn harvest is still in progress in the Corn Belt, but in the Cotton Belt cotton picking is nearly over. When the average daily temperature falls
to 35°, corn harvest is practically over, and the first snow usually has fallen. In most of the Florida Peninsula and in extreme southern Texas the average daily temperature remains throughout the year above 55°; in
southern South Carolina and in the Gulf States south of latitude 33°, in southwestern Arizona, and along the California coast as far north as Eureka it remains about 45°, and throughout nearly all the Cotton Belt, in
southern New Mexico and Arizona, in the valleys of California, and along the Pacific coast it remains above 35°
25
TEMPERATURE
Figures 81 82 83, and 84 show the average daily range in temperature for the months of January, April, July, and October, respectively. They represent the difference between the average of the maxima and the
average of the minima temperatures of each day of the month. In January the least daily range is in the Puget Sound region, where it is less than 9° F„ and the greatest daily range is in southern New Mexico and
Arizona where it is over 33°; in April the least daily range, 9° to 12°, is along the western Gulf, southern Florida, northern California, and southern Massachusetts coasts and the greatest daily range, over 39 ,isag i
in southern New Mexico and Arizona; in July the least daily range is along the north Pacific coast, and the greatest, over 42°, is in southern Oregon and northern Nevada; and m October the least daily range is m southern
Florida and along the north Atlantic and north Pacific coasts, and the greatest is in northern Nevada. The equalizing influence of large bodies of water ,s everywhere evident, especially m July, and conversely the
large daily range in temperature in arid climates is very apparent. In general the daily range in the interior of the country east of the Rocky Mountains ranges mostly between 20 and 30 , except around the Great L e ,
being smallest in winter and largest in late summer and fall, when the weather is driest
or the highest and the lowest temperatures ever recorded
in the respective months.
Seasonal temperatures.— Of these the most important
are the average summer and average winter tempera¬
tures. The average summer temperature is especially
significant because in the more northern portions of the
United States and at higher altitudes in the West the
three summer months coincide more or less with the grow¬
ing season of potatoes and of corn, whereas the average
winter temperature shows many interesting correlations
with the northern limits of winter wheat and several
tree fruits. Figure 2 shows the average summer and
Figure 5 the average winter temperature.
Average annual temperature.— The true average annual
temperature is the average of the 365 successive average
daily temperatures (24-hourly observations), but it is
customary to compute it from the 12 monthly averages,
based on the mean of the daily maximum and minimum.
The difference between the results obtained by these two
methods, due principally to the inequalities in the lengths
of the months, is negligible, amounting generally to a
very small fraction of a degree only.
The average annual temperature has relatively little
value as an index to the actual temperature conditions
in any locality, because of the great difference in seasonal
variations in different sections of the country. For ex¬
ample, the mean annual temperatures at San Francisco,
Calif., and at Wichita, Kans., having practically the
same latitude, are nearly the same—about 55° F. The
average daily minimum temperature at Wichita, how¬
ever, for the three winter months is 24° as compared with
46° at San Francisco, and the average daily maximum
for the three summer months at the former is 88° and
only 65° at the latter. The average January tempera¬
ture at San Francisco is 50° and at Wichita 30°, whereas
the average July temperature is 57° at San Francisco and
79° at Wichita, There is obviously little similarity in
the general temperature conditions at these two points,
yet their annual averages are the same. For these rea¬
sons no chart showing the average annual temperature
is included in the Atlas.
Average annual range. —The average annual range in
temperature is defined as the difference between the
average temperature of the coldest month and that of the
warmest month. It affords an excellent expression of
the rise in temperature that takes place from midwinter
to midsummer. At Bismarck, N. Dak., the average
Figure 85.—This graph shows for selected stations, representing
marine, continental, arid, and mountain types of climate, the average
daily march of temperature. The amplitude of the daily march of tem¬
perature thus represented is considerably less than the average daily
range in temperature, shown in Figures 81 to 84, particularly during
the winter months, since the daily march represents the average tem¬
perature for each hour of the day, whereas the daily range is based
on the daily extremes in temperature regardless of the hour of occur¬
rence. The small daily variations in temperature in marine climates
are shown by the graphs for San Francisco, North Head, Galveston,
and to a less extent by that for New Orleans, the larger daily march in
continental climates by the graphs for Cincinnati and Bismarck, and
in mountain climates by the graphs for Helena and Santa Fe, and the
still greater difference between day and night temperatures in arid
climates by the graph for El Paso. The graph for Salt LakeXity
shows the marked influence of so small a body of water as Salt Lake
in moderating the daily march of temperature
temperature of the coldest month, January, is 7° F. and
that of the warmest month, July, is 70°, making an
average annual range of 63°, whereas at San Francisco
the average annual range is only 10°.
The greatest average annual range in temperature
occurs in the northern interior districts of the United
States and the least near the coasts, especially along the
Pacific coast. In the Gulf and South Atlantic States it
is about 30° F.; in the Middle Atlantic States, central
Mississippi Valley, and the Rocky Mountain region it is
from 40° to 50°, and from Montana eastward to the
Lake region it is between 55° and 65°. The average
annual range in temperature is shown graphically for
different sections of the country in Figure 72.
ANNUAL MARCH OF TEMPERATURE
This is represented by the successive average daily
temperatures. The change in the angle of inclination
of the sun’s rays and consequently in the length of the
day is very slight for successive days and the resulting
normal change in temperature from one day to another
in the progress of the season is correspondingly small.
In individual years the temperature fluctuations occa¬
sioned by the passage of cyclonic storms so disguise this
gradual change that its occurrence can be realized only
after the lapse of a number of days. (See fig. 86.)
As in the daily temperature march, there exists in the
annual march of temperature, outside the equatorial
region, a single maximum and a single minimum. In
the United States the warmest month is July, except
along the immediate Pacific coast where, because of the
marine influence, it is often August or September, and
the coldest month is January. The occurrence of these
maximum and minimum temperatures is in general about
a month later than the time when the sun reaches its
highest and lowest altitude, respectively.
The progress of the seasons may be briefly summarized
by months as follows:
January. —The average January temperature is shown
for the different sections of the country in Figure 12. It
varies greatly in different localities and the gradient
from north to south is much steeper than in the warmer
seasons of the year. The coldest weather occurs, as a
rule, in the northern portions of Minnesota and North
Dakota, where the average January temperature is near
0° F. Southward the temperature increases rapidly,
the monthly average rising to the freezing point at ap¬
proximately the latitude of the lower Ohio River, central
Missouri, and southern Kansas, and to about 55° along
26
27
ATLAS OF AMERICAN AGRICULTURE
TEMPERATURE
DAILY MAXIMUM AND MINIMUM TEMPERATURES AT SELECTED STATIONS
F
100
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JANUARY
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FEBRUARY
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FigurL 86. This graph shows for selected stations, reprt senting the principal types of climate in the United States, the daily maximum and the daily minimum temperature for the years 1913 and 1914. In this graph the tops of the vertical bars show the daily maxima and the bottoms of the bars the daily minima. The lengths of the bars indicate the amplitude of the daily range, and the centers show the daily mean temperatures. The relative position of the bars
or successive <. ays in nates t e c a. y variability. The grapli shows the characteristics of temperature conditions for different sections of the country and for the several seasons of the year in a manner to facilitate comparison, and brings out important features not shown in maps or graphs based on average values. It visualizes, for instance, the abrupt temperature changes from day to day that may be expected to occur in the interior section of the country, especially
during certain seasons of the year and the more uniform conditions from day to day found in marine climates. For example, in the graph for Bismarck it will be noted that the maximum temperature rose above 60° F. for 11 successive days in mid-April, 1913, reaching 87° on the 14th and 89° on the 15th, and then on the 25th the minimum temperature fell to 24° and on the 26th to 20°. Such a long spell of warm weather would cause the blossoming of almost all
m s 0 1 u '*’ an t ie co wave 0 owi ng would kill the blossoms and formi ng fruit. A similar spell of warm followed by cold weather may be noted in April, 1914. Suchwidefl uctuations in temperature in the spring are characteristic of the cl i mate of the Spri ng Wheat Belt; consequently very little fruit is grown in the region. At Bismarck changes i n temperature of 40° in one day frequently occur, and on March 3, 1913, a rise in temperature from —15° to nearly 50°
occurre . e grap i or an Francisco affords a striking contrast to that for Bismarck. Changes in temperature of 30 in one day are rare, and the average daily range is only 12°. There is also very little difference in temperature between summer and winter; in fact, the difference between the average January and the average July temperature is only 9°. In 1914 the minimum temperature at San Francisco did not fall below 40° during the year, and the maximum
rose above 70 on only 47 days. The continuous high summer temperatures in the far Southwest are shown by the graph for Yuma, Ariz. It will be seen that in 1914 the daily maximum temperature in that locality was 100°, or higher, on each day from June 10 to August 29, except for 1 day, a period of practically 80 consecutive days
28
ATLAS OF AMERICAN AGRICULTURE
the Gulf coast. From the Rocky Mountains westward
to the Sierra Nevada and Cascade Ranges temperature
conditions are determined largely by altitude, rather
than by latitude as in the East. At the lower altitudes
the average January temperature ranges generally from
20° to 35°, but is higher in portions of Arizona and New
Mexico. High temperatures for the latitudes obtain
along the Pacific coast, the January average ranging
from about 40° on the extreme north coast to about 55°
in southern California.
Throughout the interior of the continent January is
characterized by frequent and abrupt temperature
changes, resulting from the passage of cyclonic storms and
accompanying anticyclones. The difference in tempera¬
ture at the front and at the rear of a pronounced cyclone
may be as great as 60° F. or more, and with rapid
forward movement of the storm the temperature at a
given place may fall 40° or 50° within a few hours.
During this month very low temperatures are some¬
times experienced in the northern interior portions of
the country. In Minnesota, the Dakotas, and Montana
temperatures of —40° to —50°, or lower, have been
recorded in January and from —25° to —35° have
occurred in the interior portions of New York and New
England. The lowest temperature ever recorded at a
Weather Bureau station in the United States was —65°
in the eastern Montana in January, 1888. Along the
central and southern California coast the lowest tem¬
peratures on record range from 27° to 29° and
along the Gulf of Mexico coast from 11° to 15°.
Freezing temperatures are of infrequent occur¬
rence along the coast of southern California
and likewise in extreme southern Florida.
February .—Figure 17 shows the average Feb¬
ruary temperature. This differs only slightly,
as a rule, from that of January, February usu¬
ally being slightly warmer. The lowest aver¬
age temperature for this month, about 5° F.,
is found in the northern portions of Minnesota
and North Dakota, whereas to the eastward
over the upper Lake region and the northern
portions of New York and New England the
average February temperature is about 15°.
To the southward there is a progressive increase
to about 32° in central New Jersey, southern
Ohio,. central Missouri, and Kansas and to
about 55° along the Gulf coast.
As in January, cold waves frequently sweep
down from the Canadian Northwest during
February and overspread all districts east of
the Rocky Mountains, sometimes bringing ex¬
tremely cold weather. In fact, the coldest
weather of the year east of the Rocky Moun¬
tains occurs frequently during the early part of
this month. A memorable cold wave occurred
in February, 1899, which carried the line of
zero temperature to the east-central Gulf coast
and a temperature of 10° F. was recorded at
Jacksonville, Fla. The coldest February tem¬
perature of record at a first-order Weather
Bureau station in the United States is —55°,
occurring in Montana in 1887. Temperatures
as low as —25° have occurred in this month as
far south as Kansas and Missouri. Toward the
latter part of the month, however, the increase
in temperature usually becomes noticeable, and
along the immediate Gulf coast freezing weather
does not occur, as a rule, after February 20.
March .—Figure 22 shows the average March
temperature. With the advent of spring there
is usually a rapid warming up in nearly all por¬
tions of the United States, although in the Paci¬
fic Coast States the increase in temperature is
not pronounced, especially along the immediate
coast. In the northern interior districts the increase in
average temperature from February to March is about
15° F., but it diminishes to the southward, being only
about half as great near the Gulf of Mexico. The aver¬
age temperature for March on the northern border be¬
tween Montana and Lake Superior is about 20°; along
the Gulf coast it ranges from 60° to 65°.
In the northern States extremely cold weather occa¬
sionally occurs during March, temperatures of —35° to
— 40° F. having been recorded in this month in portions
of North Dakota and eastern Montana. The March
cold waves, however, usually lose intensity rapidly, and
the Central and Southern States seldom experience
severely cold weather in this month. Temperatures
below zero have never been recorded in March south of
the fortieth parallel, except in the Texas panhandle,
Kansas, and a few localities to the eastward. In the
Gulf States after March 15 freezing temperatures do not
occur, as a rule, except in the extreme northern portions.
April .—Figure 27 shows the average temperature for
April. As spring advances the increase in temperature
becomes more rapid and consequently the warming
up during April is greater than during March. Along
the northern interior border of the United States the
average temperature for April is about 20° F. higher
than for March, but with progress southward the
increase becomes less pronounced, amounting to about
10° along the Gulf coast. The average April tem¬
perature ranges from about 40° in the extreme North
to about 70° at the Gulf. Along the immediate Pacific
coast there is little change in temperature from the
preceding month.
Cold periods prevail occasionally during April, espe¬
cially in the more northern districts. The lowest tem¬
peratures on record for this month are slightly less
than —10° F. near the Canadian border in North Dakota,
and freezing temperatures have occurred early in the
month as far south as Mobile, Ala., and northern
Florida. Cold waves, however, are not of frequent
occurrence during April and are of comparatively short
duration. As a rule, freezing temperature is not expe¬
rienced after April 15 south of a line extending from
central Virginia, through western North Carolina, and
the southern portions of Kentucky, westward to Mis¬
souri and Kansas.
May .—This month is characterized by the prevalence
of mild temperatures, as shown in Figure 32. The
average temperature in May ranges from about 50° F.
along the northern border of the country to 75° at
the Gulf, being from 7° to 10° higher than for April.
Along the immediate Pacific coast the average tem¬
perature ranges from 50° at the extreme north to 60°
in southern California. The highest average temper¬
ature, slightly over 80°, is found in extreme southern
Texas and in portions of the far Southwest.
The lowest temperature of record for May at a first-
order Weather Bureau station is 6° F. in the northern
portion of North Dakota. Freezing weather has been
known to occur in this month as far south as northern
Texas, and a temperature as low as 26° is on record
in the panhandle of that State. East of the Mississippi
River freezing temperature has never been experienced
in May south of the Ohio River and southern Penn¬
sylvania, except in some of the more elevated sections.
As a rule, freezing temperature does not occur after
May 10 south of South Dakota, the central portions
of Iowa and Wisconsin, and the lower Lake region.
June .—Figure 37 shows the average June tempera¬
ture. Along the northern border of the United States
the average temperature for this month is about 60° F.,
or approximately 10° higher than for May. East of
the Rocky Mountains there is a rather rapid increase
in temperature from the northern border to about 70°
at the latitude of central Iowa, and thence a less rapid
rise to about 80° in the Gulf coast section. The average
June temperature at the lower altitudes in most of the
central and northern portion of the Rocky Mountain
and interior Plateau regions ranges from about 60° to
70°, but in the extreme southern portion it is much
higher. In the lower Colorado River Valley, in the ex¬
treme Southwest, the average June temperature is over
90°, whereas along the Pacific coast it ranges from 55°
at the extreme north to 65° at the south.
High temperatures occur occasionally during June.
The highest of record at a first-order Weather Bureau
station is 117° F. at Yuma, Ariz., and records of 106°
to 110°, have been made in the Plains States and in
Montana. Temperatures of 100°, or higher, have oc¬
curred in June rather generally throughout the country,
except in the Northeastern States, the vicinity of the
Great Lakes, in the higher altitudes of the Rocky Moun¬
tain and interior Plateau regions, and along the north
Pacific coast. The average date of the last freezing
temperature in spring in the extreme northern portions
of Minnesota and North Dakota is about June 1, but
it is later than this in some of the elevated districts of
the West.
July .—Figure 42 shows the average July temperature.
This is, as a rule, the warmest month of the year, ex¬
cept in localities having the marine type of climate.
East of the Rocky Mountains the average July temper¬
ature ranges from a little less than 70° F. in the north¬
ern border States to about 82° along the Gulf coast.
The temperature gradient from north to south in the
summer season is much smaller than in the winter.
The difference between the average July temperature
along the northern border of the United States
east of the Rockies and that on the Gulf coast
is about 15°, but for January it is about 50°.
The highest July temperature in the United
States is found usually in southwestern Arizona
and the interior valleys of southern California,
where the average for the month ranges from
90° to 98°. Along the Pacific coast the sum¬
mers are cool, the average July temperature
ranging from about 55° in western Washington
to 67° in southwestern California.
In July periods of hot weather are compara¬
tively frequent in most sections of the country,
and very high temperatures are sometimes
experienced. Occasionally the hot waves are
of unusually long duration, particularly in the
sections east of the Rocky Mountains, and at
such times suffering, especially in the congested
districts of the large cities, is intense. In some
of the important agricultural districts, particu¬
larly in the Middle West, the heated periods
are occasionally accompanied by “hot winds,”
which prove disastrous to growing crops. The
highest temperature of record for July at a
first-order Weather Bureau station is 118° F. at
Yuma, Ariz., and in the Great Valley of Cali¬
fornia temperatures of 110° to 115° have
occurred. A maximum temperature of 134°
has been recorded at a cooperative station in
Death Valley, Calif., which is the highest
official temperature ever recorded in the United
States and probably in the world. In the
Plains States and Mississippi Valley tempera¬
tures of 105° to 110° have been experienced,
and records of 100° or higher have been made
generally throughout the country, except in
some restricted areas. Although the average
summer temperature in the Southern States
is considerably higher than in the Northern,
extremely hot weather occurs occasionally in
practically all northern sections of the country.
In fact, higher temperatures are on record in
the Dakotas and Montana than have ever
occurred in Mississippi, Alabama, or Florida.
August .—Figure 47 shows the average August
temperature. This differs little from that for
July, but as a rule August is slightly cooler, except on
the Pacific coast. At some points on the Pacific coast
September is the warmest month of the year. East of
the Rocky Mountains the coolest August weather occurs
in northern Michigan and in -the interior of New York
and New England, where the average temperature for
the month ranges from about 62° to 65° F. At points
in the far Southwest it is as high as 95° or more. The
remarks as to July temperature conditions in general
apply also to those of August.
September .—Figure 52 shows the average temperature
for September. The average September temperature
ranges from about 55° F. in the northern border States,
where it is about 8° lower than for August, to about 78°
along the Gulf coast, where it is 2° or 3° lower. At the
lower elevations of the Rocky Mountain and interior
Plateau regions it is mostly from 50° to 65°. In the
Great Valley of California the average September tem¬
perature is 70° to 75°, and in southwestern Arizona it
is 80° to 85°.
High temperatures sometimes occur in September,
especially between the Rocky Mountains and Missis¬
sippi River. The highest of record for this month at a
first-order Weather Bureau station in this region is
106° F., in eastern South Dakota, and temperatures of
or continuous daily records of temperature. The trace sheets for San Francisco and Yuma are
presented to contrast the daily march of temperature in the two extreme types of climate—marine
and arid continental. In arid continental climates the fall in temperature is rapid after sundown
and the rise pronounced during the morning hours, resulting in relatively cool nights and hot
days. The marine type of climate, on the other hand, is characterized by comparatively uniform
temperatures throughout the day. The trace sheet for Topeka, Kans., from July 8 to 14, 1901,
was selected to show the temperature curve during a hot wave in midsummer, and that for Kansas
City, Mo., from November 8 to November 14, 1911, to show the temperature curve during a severe
cold wave in the late fall
29
TEMPERATURE
100° or higher have been quite generally experienced.
East of the Mississippi River only a few stations have
temperature records for September as high as 100°. In
portions of California high temperatures are reported
occasionally in this month, the highest of record at a
first-order station of the Weather Bureau being 111° at
Fresno, Calif. Cool weather also occasionally obtains
in September, freezing temperatures having occurred as
far south as the southern portions of Kansas and Mis¬
souri and the Ohio River Valley. The average date of
the first freezing temperature in fall in most of the
Dakotas and Minnesota, in northern Wisconsin, and at
the higher elevations of New York and New England
ranges from September 15 to 30.
October .—Figure 57 show r s the average temperature
for October. During October there is a considerable
decrease in temperature, except in extreme southern Flor¬
ida and along the Pacific coast, the decrease being
generally as much as 10° to 15° F. Along the extreme
northern border of the country the average October
temperature is about 45°, increasing wdth progress south¬
ward to about 70° along the Gulf coast. West of the
Rocky Mountains at the lower altitudes the average for
the month ranges from somewhat less than 40° to about
50°, except that it is higher in the far southwestern
region. On the Pacific coast the average temperature
ranges from 50° at the north to 60° at the south.
Temperatures below zero have been experienced at a
few points in the north Central States in October, the
lowest of record at a first-order station of the Weather
Bureau being —16° F. in northern Montana, and freez¬
ing temperatures have occurred nearly to the Gulf coast.
On the average freezing weather occurs by the last of
October as far south as the northern portions of South
Carolina, Georgia, Alabama, and Mississippi and the
central portions of Arkansas, and Oklahoma.
November .—Figure 62 shows the average temperature
for November. During November the decrease in tem¬
perature as a rule is rather pronounced, the average for
the month being mostly from 10° to 15° F., or more,
low T er than for October, except along the Gulf and Pacific
coasts. East of the Rocky Mountains the average
November temperature ranges from about 25° in the
north-central border States to somewhat more than 60°
along the Gulf, but in southern Florida it is 70° or higher.
Along the Pacific coast the average temperature is 45°
at the north and about 60° at the south.
During November cold waves of considerable severity
sometimes advance from Canadian Northwest and over¬
spread the north Central States (see Kansas City ther¬
mograph record in Figure 87), but they usually lose
energy rapidly in their eastward and southward progress
and seldom are of long duration. Zero temperatures
have never been recorded at a first-order Weather
Bureau station in November south of the Ohio River,
but freezing has occurred as far south as Tampa, Fla.
The lowest temperature of record for this month is —33°
in northern Montana.
December .—Figure 67 shows the average temperature
for December. Temperatures, as a rule, continue to
decrease rapidly during December. East of the Rocky
Mountains the decrease in the monthly averages from
November to December range from about 15° F., in the
extreme northern portion of the country to 7° or 8° along
the Gulf coast, but along the Pacific coast December is
only 3° or 4° cooler than November. The average
December temperature is about 10° in the north Cen¬
tral States, about 55° along the Gulf coast, and 70° in
extreme southern Florida. In the lower altitudes of
the Rocky Mountains and interior Plateau regions
the average December temperature is mostly between 20°
and 30°, except in New Mexico and Arizona, where it
is locally as high as 55°. Along the Pacific coast it
ranges from 44° to 56°.
During December cold waves usually become more
frequent and severe, and very low temperatures are
occasionally experienced in much of the interior portion
of the country. The lowest temperature of record at a
first-order Weather Bureau station for this month is - 50°
in northern Montana, while temperatures of —10° to
— 15° have been experienced as far south as the southern
portions of Kansas and Missouri, and —5° in portions
of Tennessee and North Carolina. The lowest recorded
temperature along the Gulf coast in this month is 14°,
occuring at Mobile, Ala., and also at Pensacola, Fla.
Along the central and eastern Gulf coasts the average
date of the first freezing temperature in fall is about
December 1.
SIGNIFICANT TEMPERATURES
Figures 73 to 80 show the progress of the season with
reference to certain significant temperatures. The
averages dates in spring on which the daily mean tem¬
peratures rises above 35°, 45°, 55°, and 65°, F. in
different portions of the country are shown by Figures
73 to 76, respectively, whereas Figures 77 to 80 show the
average dates in fall when the daily means fall below these
values.
Figures 3 and 6 show for the different sections of the
United States the highest and lowest temperatures ever
recorded, and Figure 4 shows for selected stations the
highest temperatures recorded each year for the 20-year
period—1895-1914.
Figure 7 shows the average of the lowest tempera¬
tures recorded each year, and Figures 8 and 9 show the
number of times in the 20-year period—1895-1914—that
the minimum temperature each year was 6° and 9° F.,
respectively, below this average minimum.
Figure 10 shows the average annual number of days on
which the minimum temperature falls to freezing and
Figure 11 the average annual number of days with
temperature continuously below freezing for the entire
day.
AVERAGE MONTHLY TEMPERATURES
[Monthly mean temperatures]
AT SELECTED STATIONS
ALABAMA
Dudleyville_
Flagstaff_
Fort Apache_
Fort Grant_
Fort Huachuca.
Fort Mohave_
Oila Bend_
Grand Canyon..
Holbrook-
Jerome...
Parker...
Phoenix...
Salome..
Tucson *_
Yuma_
Bee Branch.
Brinkley-
Camden_
Dodd City..
Fayetteville-
Fort Smith_
Helena__
Hot Springs-
Jonesboro_
Junction_
Little Rock-
Mena..
Newport_
Pine Bluff_
Pocahontas.
Portland....
Texarkana-
Bagdad-
Bakersfield-
Barstow-
Bishop....
Branscomb_
Cedarville-
Colusa__
Crescent City-
Escondido_
Eureka.
Fresno..
Georgetown-
Greenland Ranch.
Hollister...
Indio__
King City-
Lodi..
Los Angeles.
McCloud_
Merced..
Mojave...-
Napa.
Orleans--
Red Bluff-
Redlands-
Sacramento-
San Diego-
San Francisco-
San Luis Obispo. .
Santa Barbara-
Sterling-.
Susanville.
Ukiah-
Yosemite-
Stations
January
| February
March
| April
>>
03
<<
| June
July
j August j
j September j
October |
1 i
j November
J December j
1 Length of
record
1 (years) )
Anniston __-
43.7
44.
7
,54.1
60.8
68.9
76.0
78.0
77.8
73.2
62.8
51.6
44.
0
29
Birmingham._ . ..
46.0
46.
4
56.6
62.7
71.8
78.0
80.0
79.8
76.3
65.2
54.4
45.
8
33
Decatur_
41.8
42.
8
53.2
61.6
69. 9
77.5
79.8
78.7
73.1
61.6
60.5
42.
5
39
Fort Deposit .
47.2
48.
7
58.1
64.9
73.3
79. 4
81.2
80.2
76.1
65.5
55.3
47.
4
37
Goodwater... _ ..
44.6
44.
9
55.8
62.1
71.2
77.8
79.7
79.4
75.2
64.0
53.6
44.
5
26
Greensboro_ .
46.0
48.
4
56.2
63.6
71.6
78.6
80.1
79.5
75.3
64.7
55.1
48.
1
39
43.0
43.
5
54.0
60.5
69.5
76.6
79. 0
79.7
74.9
62.5
52.5
44,
0
22
51.2
53.
9
60.1
66.6
73.9
79.9
81.4
81.0
77.6
68.4
58.8
52.
3
50
Montgomery.__
48.4
51.
0
58.3
65.2
73.2
79.9
81.6
80.7
76.3
66.2
55.9
49.
0
49
Opelika_ _
46. C
47.
5
56.6
63.6
71.9
78.5
80. 1
79.1
74.6
64.1
54. 5
46.
2
39
Ozark__
49.5
50.
4
60.6
65.3
73.9
79.6
80. 7
80. 8
77.1
67.1
56.9
49.
9
19
Seottsboro.. .
41.9
42.
4
52.6
60.1
68.1
75.1
77.9
77.2
71.9
61.0
50.2
42.
4
36
Thomasville . _
47.6
49.
1
o8.3
64.4
72.7
79.4
80.8
80.4
76.0
65.0
55.4
48,
1
29
Tuscaloosa.. ---
44.4
45.
4
55.41
63. C
71.1
79. C
81.3
80.6
75.7
64.2
52.8
45.
9
39
Tuscumbia..
41.0
42.
4
52.4
60.9
69.3
77.3
79.9
78.7
72.9
61,2
50.4
42.
4
39
ARIZONA
ARKANSAS
CALIFORNIA
COLORADO
48.2
51.4
56.3
62.4
69.1
78.6
83.0
81.4
76.1
65.3
55.0
47.5
28
27.8
30.4
36.1
43.2
50.0
59.3
65.2
63.7
56.6
46.4
37.0
28.6
27
34.6
36.9
43.6
51.8
57.7
66.3
71.2
70.1
63.9
53.8
43.4
36.6
40
45.1
48.0
52.5
58.8
66.9
76.0
78.9
75.2
72.3
63.4
o4. 0
47.0
24
46.2
48.3
55.0
60.0
66.6
76.4
76.6
74.8
71.2
63.3
52.6
45.8
32
49.8
56.2
62.6
70.2
78.1
87.2
93.8
91.6
84.2
71.6
59.8
50.6
21
53.9
56.5
63.2
68.0
75.2
86.3
92.0
91.0
85.2
72.9
62.0
52.1
22
28.5
32.0
36.2
43.7
49.4
61.6
76. 6
65.4
57.9
47.9
38.6
29.6
15
33.1
39. 7
45.7
52.6
60.4
70.2
75.6
74.7
67.2
63.8
43.2
34.2
24
42.2
45.6
50.6
58.0
64.6
76.2
78.8
76.7
72 4
61.6
51.8
43.0
22
49.8
55.4
61.4
68.6
75.4
84.8
90.9
90.4
82.9
70.3
58.2
49.5
25
51.8
55.6
60.1
67.0
73.9
84. 6
89.2
88.0
82. 4
70.4
59.8
51.3
27
47.0
50.5
56.0
62.4
69.2
81.2
86.6
85.6
78.8
66.6
56.4
46.8
13
50.0
52.6
57.8
63.5
71.9
81.3
85.6
83.6
79.3
67.9
57.6
49.9
35
54.4
58.6
64.1
69.5
76.2
84.7
90.8
90.4
83.7
73.3
62.4
55.2
40
41.3
42.1
52.6
60.9
68.6
76.8
80.0
79.4
74.4
62.6
51.3
42.2
29
41.8
43.0
52.4
60.7
70.0
77.7
80.8
80.2
74.6
62.1
51.8
43.4
35
44.9
47.0
56.0
63.7
71.2
78.2
81.0
80.2
75.4
63.7
52.2
45.1
31
37.6
37.8
47.6
58.7
66.9
74.6
78. 1
77.5
71.8
60.0
48.9
39.2
28
38.0
39.3
49.9
58.0
66.2
74.2
78.0
77. 6
72.4
60.9
49.8
39.9
31
39.5
42.8
51.3
61.7
69.7
78.0
81.0
79.4
72.7
61.7
49.9
41.7
41
43.0
43.6
53.8
62.4
70.8
78.2
81.3
80.6
74.8
62.5
53.2
44.8
30
43.2
46.8
53.9
62.9
69.8
77.6
81.3
80.0
75.2
64.0
52.7
44.6
25
40.4
41.5
52.8
61.2
69.8
77.6
79.9
79.9
74.3
62.5
51.4
41.0
26
45.6
47.1
57.2
65.6
71.8
79.4
81.9
80.8
75.6
64.2
53.9
46.1
28
41.8
44.2
53.6
62.4
70.0
77.6
80.8
79.7
74.2
63.5
52.3
44.0
43
41.3
43.6
52.0
61.4
68.9
76.4
79.8
79.4
73.8
62.8
53.1
42.6
30
39.2
40.5
52.6
61.8
70.0
77.8
81.0
79.8
73.8
61.4
51.0
41.9
34
43.1
45.4
54.8
64.4
72.0
79.0
82.2
81.4
73. 1
62.6
52.8
44.4
34
38.0
40.4
51.6
60.0
68.6
78.0
81.7
81.0
74.8
62.9
51.2
40.8
28
46.3
48.5
58.8
63.7
71.3
79.2
81.5
81.1
76.4
64.8
53.9
47.4
16
46.2
47.8
56.8
63.8
71.6
79.0
82.3
81.9
76.8
64.6
55.4
46.8
36
Avon Park.
62.6
63.2
68.8
71.9
77.0
80.0
81.4
81.6
80.2
75.2
68.1
62.6
Clermont..--
60.9
62.5
68.8
72.3
78.2
81.6
83.0
83.0
80.8
75.2
67.9
61.4
Fort Meyers_
63.0
64. 2
68.6
71.8
76.6
79. 4
80.6
81.0
79.8
75.4
69.0
63.7
Fort Pierce ..
64. 0
64.4
68.5
71.4
75.9
79.3
80.8
81.4
80.2
76.4
69.4
64.1
Jacksonville..
55.8
57.6
63.2
68.6
74.8
80.0
81.9
81.6
78.4
70.8
62.5
56.4
Key West..
70.0
70.6
72.8
75.6
79.0
81.9
83.5
83.6
82.2
79.0
74.2
70.2
Lake City....
Miami...
55.6
56. 9
64.4
68.8
75.5
79.7
81.0
81.1
78.6
70.6
62.0
56.0
67.0
67.6
71.1
73.6
77.8
80.2
81.7
82.0
81.0
77.8
72.8
68.4
Ocala...
58.0
58.9
65.4
69.3
75.8
79.9
81.0
81.2
79.0
72.1
63.4
57.8
Pensacola....
53.0
55.0
60.8
66.8
73.6
79.4
80.8
80.8
78.2
69.6
60.4
54.4
St. Augustine_
57. C
58.0
63.6
68.1
74.0
78.9
80.8
80.6
78.8
73.2
64.3
58.0
Tallahassee_ ..
53.7
54.5
62.2
67.2
74.6
79.4
80.2
80.1
77.4
69.4
60.2
53.6
Tampa....-
Titusville.
60.8
62.7
67.0
71.6
76.6
80.0
81.1
81.2
79.8
74.2
67.2
61.7
60.4
61.9*
65. 1
69.4
75.0
78.8
81.0
81.3
79.4
74.0
66.4
61.3
52.8
57.1
63.8
72.8
79.1
89.1
95.2
93.8
84.2
65.9
61.1
52.5
17
47.4
52.2
56.3
62.6
69.7
77.8
84.0
81.8
74.1
65.4
55.7
47.9
34
46.3
50.4
56.4
61.8
67.4
77.8
83.6
82.4
74.2
64.0
54.2
45.9
17
37.0
41.6
46.2
52.9
59.0
66.9
72.8
71.4
63.9
55.0
45.6
38.0
22
42.6
44.2
45.9
49.8
53.4
59.2
66.4
66.1
61.9
57.0
49.0
43.6
18
29.7
33.0
38.6
46.5
52.6
31.4
70.3
69.0
60.0
49.6
39.5
30.6
27
45.6
49.4
53.5
58.2
64.7
71.8
76.8
75.2
69.7
61.8
52.3
44.9
20
46.2
47.0
48.0
50.0
52.2
55.7
57.8
58.1
57.8
54.9
50.5
46.6
22
50.0
52.1
55. 1
58.5
62.5
38.4
72.5
72.4
68.9
62.3
56.1
50.4
26
46.8
47.1
48.2
49.8
52.0
54.4
55.6
56.2
55.6
53.5
51.0
47.8
37
46.2
51.1
54.8
60.5
66.6
75.2
81.9
30.5
73.5
64.4
54.5
46.4
35
42.4
44.4
47.1
52.6
56.6
66.1
74.4
73.6
67.5
58.9
50.1
44.5
20
52.9
58.2
65.5
75.3
82.6
94.5
101.2
99.0
89.7
74.8
60.9
52.1
9
48.1
51.2
53.6
56.8
60.2
64.4
66.1
65.8
65.0
60.4
53.9
48.9
49
53.4
58.7
65.0
72.4
79.0
38.0
93.6
92.4
85.9
75.2
62.8
55.5
42
49.1
50.7
54.2
57.5
61.2
65.1
68.2
68.7
67.7
61.8
55.4
50.5
35
46.2
50.1
54.7
58.3
63.4
69. 1
73.7
73.0
69.7
62.3
53.6
47.3
30
54.5
55.5
57.3
59.7
62.1
65.2
70.2
71. 1
69.4
65.1
60.9
55 3
42
34.0
36.6
40.4
45.8
51.9
59.0
63.9
64.0
57.4
50.0
42.2
?-o. 0
13
46.3
49.5
53.2
59.4
66.1
74.4
80.6
78.8
72.7
63.6
54.0
47.2
49
46.0
49.0
52.2
59.5
68.0
77.4
85.5
83.7
76.3
65.7
54.6
47.2
37
46.8
50.1
52.2
55.8
59.2
64.9
66.8
66.2
65.6
61.0
53.4
47.8
25
44.8
48.4
53.fi
59.0
62.8
67. 5
76.3
75.8
69.0
60.4
51.4
45.0
18
45.4
49.5
53.8
59.3
66.2
74.8
81.3
80.0
73.2
63.6
54.0
46.2
46
50.9
52.7
55.8
60.1
63.6
71.4
76.8
76.6
72.2
65.4
58.2
52.2
27
45.2
49.8
53.5
58.1
63.3
70.2
73.9
73.3
70.3
62.7
53.3
46.5
46
54.3
55.0
56.9
59.2
61.3
64.8
68.1
69.7
67.9
63.9
59.5
55.7
68
50.0
52.3
53.6
55.2
56.5
58.5
58.5
59. C
61.2
60.3
56.3
51.2
52
51.9
53.5
54.6
56.2
57.4
61.9
64.2
64.7
64.4
62.1
57.5
53.0
28
53.4
54.4
55.6
57.7
59.1
62.3
65.5
66.7
65.7
62.7
58.8
55.1
38
54.2
58.8
04.8
73.8
80.4
90.0
97.8
94.8
88.3
74.4
64.0
55.1
42
30.3
34.6
40.0
47.6
52.7
61.2
68.2
67.4
59.0
49.9
40.4
'31.6
20
44.5
47.8
50.2
55.1
59.2
65. i
71.7
70.9
,65.9
60.0
50.2
44. 6
27
32.6
38.4
43.6
50.6
54.7
63.0
69.4
68.4
62. C
53.3
41.6
33.8
16
Alapaha_
Albany.
Americus.
Athens_
Atlanta_
Augusta..
Eastman_
Fort Gaines...
Gainesville_
Griffin_
Louisville_
Macon...
Newnan_
Rome_
Savannah.
Thomasville..
Way cross_
Ashton_
Boise.
Buhl..
Cambridge....
Idaho Falls.
Koosjia_
Lakeview_
Lewiston.
Mackay_
Oakley..
Payette_
Pocatello.
Pollock_
Porthill_
St. Maries_
Salmon_
Stations
January
February
March
a
<
May
©
a
3
£
3
3
O
September
October
November
December
Length of
record
(years)
Stations
January
j February
| March
April
a
g
<D
fl
3
July
| August
| September
| October
| November
| December
Length of
record
15.4
15. 6
22.4
30.0
39.0
48.6
53.4
53.0
46,6
35.9
25.6
15.2
22
Cairo---
35.7
37.8
47.6
58.3
67.6
75.5
79. 1
77.6
71.0
59.9
47.7
38.5
4
27 8
31.4
40.2
47.6
57.5
68.4
73.6
72.5
64.8
52.0
40.6
29.0
18
Carlinville_
28.6
29.8
42.7
53.9
64.0
73.0
76.8
75.7
69. 0
56. 5
43.3
32.0
3
35.3
35.2
42.9
50.0
57.4
66. 1
72.9
72.3
64.3
53.1
43.4
35.9
29
Charleston_
28. 2
29.6
41.2
52.9
63.4
72.6
76.5
74.3
68.3
55. 7
42. 6
32. 0
3
28.0
30.0
39.4
48.6
58.1
68.4
73.7
72.8
64.8
52. 4
39.5
28.0
26
Chicago..
24.3
25.9
35. 6
46. 7
57.0
66.9
72.7
71. 6
64.9
53. 6
39. 8
29.1
30.0
29.6
37.5
44.6
53.1
62.0
67.0
66.2
59.6
48.8
38.7
30.6
29
Dixon_....
20.0
21.5
35.2
48. 6
59. 6
69.1
73.9
71. 8
64. 2
51. 7
37.4
25.0
3
24 5
31.6
41.8
50.5
59.0
68.0
74.0
71.5
62.6
50. 4
38.8
25.6
28
Flora_
31.2
31.0
43.2
54.3
63.9
72.8
77.0
75.0
68. 2
56. 3
43. 4
34.0
3
30.2
32.2
39.2
47.2
56.4
66.6
72.0
70.9
62.6
51.2
39.7
32.2
51
Galva---
21.8
22.6
37.3
49.2
60.8
70.0
74.8
72.7
65.3
53.4
38.7
25.9
25. 5
30.0
37.6
45.2
52.7
61.4
67.2
66.2
58.9
48.1
38.6
26.9
28
Griggsville....
27.0
28.9
41.5
53.7
63.9
72.7
76.9
75.2
67.9
56. 2
42.8
31.3
3
26.2
27.4
36.0
44.8
53.8
63.1
68.0
67.5
59.2
48.0
30.1
27.2
28
MeLeansboro_
31.6
34.0
44. 7
55.4
65. 2
74.2
77.9
76. 1
69. 8
57. 8
45. 3
35. 5
3
25. 5
32.8
43.5
52.2
61.0
71.6
77.4
75.4
66.4
53.1
40.2
27.6
31
Marengo..
18.8
21. 1
31.8
45.9
57.4
67. 1
71.8
69.6
61.9
49. 4
35. 0
23. 5
26.0
27.8
38.0
47.4
56.8
66.6
70.9
70.0
61.2
49.1
36.6
26.0
28
Peoria_
23.6
26.9
37.2
49.9
61.1
70.2
74.3
72.4
64. 9
52. 7
38. 7
27.9
7.2
12.4
25.6
39.2
47.6
57.6
61.4
59.8
52.0
41.4
27.6
10.8
29
Pontiac---
25.3
26.6
39.0
50.7
61.6
70.7
75.8
73.6
66.4
54.0
41. 5
29. 4
27.0
27.5
36.0
44.9
53.4
62.4
67.6
66.8
58.8
47.4
36.3
27.0
27
Sparta.....
32.4
33. 5
45. 1
55.8
65.4
74.1
77.8
76. 1
69.7
57.9
45. 5
35. 5
3
32.2
33.2
40.8
48.4
56.7
66.8
71.4
70.2
63.2
52. 3
42.4
31.1
21
Springfield_
26.9
29.0
40. 5
52.8
63.2
72.3
76.6
74. 5
67.3
55.9
42.3
31. 5
4
Holyoke _ __
28.6
2678
37.2
47.2
57.2
66.9
73.1
71.8
62.8
50.0
39.0
26.8
14
Urbana_
25.6
26.8
40.0
49.6
61.1
69,7
74.5
72.9
65. 8
54.2
41. 7
28.8
27.0
29.2
42.1
51, 4
61.0
71.8
76.0
72.8
66.1
53.2
40.2
29.7
36
Lay...
18.4
20.8
32.1
41.4
49.8
59.4
66.6
65.0
55.6
44.1
32.3
20.6
25
20.5
24.0
34.2
43.0
51.1
59.2
64.8
63.4
55.2
44.1
33.2
20.9
29
INDIANA
30.8
32.3
41.4
49.8
59.0
69.0
74.0
73.3
64.8
52.5
40.3
31.8
34
21.5
27.0
35.4
44.3
52.0
60.8
65.5
63.9
57.0
46.8
34.8
22.4
27
21.0
25.8
34.2
41.7
49.3
57.8
62.4
61.4
54.8
44.4
33.2
22.5
29
Cambridge City....
27.2
27.2
39.9
49.8
60.6
69.2
73.6
71.4
65.1
53.0
40.6
30.0
3
31.4
32.6
42.5
51.4
61.1
71.2
76.2
75.2
67.6
55.1
42.8
32.2
29
Elliston___
29.5
31.7
43.4
54.0
63.7
74.3
75.7
73.9
67.7
56. 0
43.7
33.3
3
29.2
30.4
39.8
48.8
59.0
69.4
74.4
73.1
64.4
51.8
39.4
29.5
25
Evansville__
34.4
34.5
45.0
55.8
66.8
75.4
79.1
77.6
71.7
60.0
47.4
37 . 2
:
Fort Wayne__
26.5
25.8
38.6
49.2
60.8
68.9
73.9
71.3
65.2
53.8
40.8
28.3
2
Indianapolis _
28.6
30. 4
40.6
52.2
63.1
72.1
76.1
73.9
67.1
55. 4
42. 1
25.6
27.1
38.6
50.5
61.7
70. S
74. S
72.8
66.2
53.9
40.4
29.6
-
CONNECTICUT
Logansport...--
25.2
29.3
37.8
50.8
62.2
71.2
75.4
72.8
65.9
53.2
40.6
29.2
3
32.:
34.'
45. (
55. (
64 .4
75.4
76.1
74. 5
68.6
56.7
45.0
35.1
3
Scottsburg.. ... - ..
33. C
33.0
45.3
54.8
65.5
74.0
78.4
75.9
69.7
57.3
45. 1
34.8
S
Cream Hill..
23.1
21.6
32.7
43. (
55.2
63.8
69.2
66.4
60.9
50.9
36.9
25.7
20
South Bend.
24. J
23.6
36.7
48.i
60. (
68.9
73.5
71.6
65.4
53.4
40.0
27.8
5
Hartford.
27.6
25.7
36.4
47.c
58.5
66.7
72.8
70.2
63.4
53.9
41.5
30.8
16
Terre Haute.
30.5
30.5
43. (
53.9
65. (
73.5
77.5
75.7
69.4
57.5
44.5
33.0
New Haven_
29.2
28.9
36. (
46.1
57.8
66.5
71.9
70. C
63.7
53.4
41.9
32.5
48
Valparaiso_
23.
123.5
36.'
48.'
58.2
64.6
72.7
70.8
65.1
53.4
38.8
27.5
Grosvenor Dale....
24.3
23.0
34.6
45.4
56.fi
64.4
70. £
68.2
58.4
51.2
39. C
28. C
18
Vevay__
32. 7|34.
42.5
53.8
65.3
73.8
77.5
75.5
69.6
57.5
45.6
36.1
ILLINOIS
FLORIDA
GEORGIA
50.4
52.0
59.8
66.2
74. 1
79.7
81.3
80.9
76.9
67.4
57.5
50.7
49.9
51.5
60.3
66.7
74,7
80.8
82.2
81.6
77.6
67.9
57.8
50.8
48.3
50.3
58.5
65. 1
73.6
79.9
81.4
80.8
76.5
66.7
56.1
49.0
42.5
44.4
52.3
60.8
70.0
76.7
79. 0
78.0
72.7
62.0
51.5
43.6
43.0
45.1
52.5
60.6
69.2
75.8
78.4
77.2
72.2
61.9
51.8
44.4
47.1
49.9
56.2
64.2
72.5
78.8
81.3
79.8
74.8
64.5
54.3
47.3
49.6
50.1
59.5
65.9
74.0
80.0
81.6
80.9
76.7
66.7
56. 7
48.8
49.0
50.4
59.3
65.7
73.9
80.0
81.4
80.8
76.7
66.8
56.7
49.8
41.2
42.4
51. 5
59.2
68.1
74.8
77.7
76.2
71.0
60.8
50.6
42.0
44.7
45.9
55.8
62.8
71.2
77.8
79.8
78.8
74.3
63.8
53.7
45.1
47.2
48.8
57.0
63.9
73.0
78.7
80. 5! 80. 0
75.4
65.1
54.7
47.5
47.3
48.5
56.6
63.9
72.3
78.8
81.1180. 0
75.3
64.8
54.2
46. 7
44.1
44.8
54. S
61.4
70.9
77.7
79. 6178. 7
73.9
63.4
53.1
44.4
41.5
43.8
52.4
60.7
69.7
76.5
79. 2|78. 4
72.9
62.2
50.3
42.5
51.8
53.7
59.6
06.3
73.8
79.2
81.5:80. 7
76.4
67.3
58.3
52.2
52.5
53.8
61. 1
66.8
74.6
79.9
81.4 81.1
77.4
68.4
58.8
52.4
52.0
52.8
61.2
67.0
74.6
80. 1
81.9|81.4
77.5
68.7
58.7
51.5
IDAHO
IOWA
KANSAS
50
28
60
65
22
28
29
30
23
40
Algona___
15.7
17.5
32.1
47.5
58.8
68.6
73.1
70.8
62.5
50.2
34.1
21.0
29
Charles City_
14.2
16.4
31.8
46.4
57.9
67.2
72.3
69.9
62.0
49.7
33.8
21.0
29
Clarinda--
21.9
23.5
37. 1
50.3
61.0
71.0
75.9
74.2
65.9
53.6
38.7
25.8
31
Corydon--
23.2
24. 1
38.3
50.6
01. 1
70.2
75.3
74.1
64.8
54.8
40. 1
26.4
27
Cresco.
10.6
14.7
27. 1
44.4
56.5
65.7
70.6
69.0
59.9
47. 1
29.7
18.2
33
Davenport_
21.4
24.3
36.2
49.9
61.2
70.6
75.5
73.2
65.3
53.3
38.5
27. 1
49
Denison...
19.8
20.5
35.1
48.6
59.3
68. 5
73.4
71.8
63.7
52.2
36.8
23.8
25
Des Moines...
20.1
23. 1
36.3
50.3
61.2
70.5
75.4
73.3
65. 1
53.5
38.4
25.8
42
Dubuque-- ... -
18.5
21. 5
34. 1
48.7
60.2
69.1
74. 1
71.7
63.8
51.8
36.8
24.9
47
Greenfield..
20.8
21.8
35.8
49.6
60.4
70.0
74.4
72.8
65.0
53.0
37.8
25.5
28
Independence..
16. 7
18.6
34.0
47.5
58.8
67.4
72.6
70.5
62. 9
51. 1
35.8
22.0
27
Keokuk- -
24.2
27.2
38.8
52.7
63. C
72.6
77.0
75.4
67.2
57.0
41.8
30.2
49
Logan..
21.0
22.8
36.5
50.6
61.0
70.3
74.9
73.2
65.1
52.7
37.7
25.7
31
Marshalltown___
18.6
19.9
34.7
48.5
60. C
69.0
74.1
72.2
64.1
52.1
37.1
23.1
26
Rockwell City-
18.4
19.5
34.6
47.4
59.2
69.0
73.8
71.7
63.4
51.7
36.4
22.4
24
Sibley---
13.9
15.2
30.6
45.8
56.7
66.0
70.3
68.9
60.3
48.7
32.7
19.2
25
Sioux City_
18.7
20.0
33.8
48.7
59.7
69.4
74.4
72. 1
63.9
51.6
36.0
24.2
31
Washington...
21.4
22.9
37.3
50.2
61.1
70. 1
74.7
72.9
65.1
53.4
38.7
25.7
28
Colby..
28.8
30.4
40.1
50.2
59.7
70.1
75.7
75.0
66.3
53.7
41. 1
29.5
25
Concordia- .
24.4
28.8
40.7
53.6
63.7
72. 7
78.1
76.5
68. 1
55.4
39.9
29.7
25
Dodge City.
29.0
33.2
42.8
53.6
63.5
72.5
78.4
77.7
69. 4
56. 1
42.6
32.6
25
Ellenwood..
30.5
32.5
44.4
54.2
63.7
73.5
78.7
78.3
70. 1
57.7
44. 1
31.8
25
Emporia.
31.0
32.5
45.3
.54.5
64.4
73.3
78.2
77.4
69.7
58.2
45. 8 32. 8
25
Hanover..
27.4
30. 1
43.0
52.8
63.0
73.0
79.0
77.0
68.7
57.3
43. 1
29.7
25
Hays ..
29.8
31.0
42.3
51.8
61.6
71.9
77.9
77.2
68.3
56.0
42.2
30. 6
25
Healy.
28.9
32.2
42.5
51.8
61.5
71.4
76.5
76.3
68.2
55. 5
42.7
30.4
25
Horton.-
27.2
28.3
41.6
52.2
62.6
72. 1
76.9
76.0
67.8
56.7
43. 1
29. 4
25
Independence..
34.6
35.9
48.5
57.4
67.0
75.8
80.1
80.0
72.5
60.6
48.4
30.2
25
T fll A
27.6
32. C
42.4
54.2
64.5
73.4
78.1
76.3
68.6
56.9
43.0
32.5
25
Medicine Lodge -
33.0
35.4
47.4
56.9
66.5
75.6
80.5
79.9
72.0
59.8
47.0
34. 1
25
Phillipsburg....
27.8
30.3
42.4
51.9
61.9
72.8
77.9
77.6
68.7
56.2
44.4
29.6
25
Salina. ...
29.1
31. C
44. C
54.3
64.2
73.8
79.3
78.8
70.5
57.8
44.0
31.0
25
Topeka..—-
25.6
30.0
40.9
53.7
65. C
73.5
77.6
76. C
68.3
56.3
41.7
31. 1
25
Ulvsses__-
31.0
32.8
43.9
53. C
62.6
73.1
77.7
77.6
69.5
56.8
42.9
31.2
25
Wichita.
29.7
33.0
44. 1
56.6
65.9
74.3
79.0
77.5
69.8
58.8
43.8
34.2
25
18. 6! 21. 4
29.0
41.0
48.6
57.0
64. 4
63.4
54.4
43.3 32. 2
20.5
24
KENTUCKY
29 fi!34. 7
44.0
50. 5
57. 4
65. 1
73. 1
71.9
61. 6
51.0|40. 4
32.4
58
28.4
32.9
40.7
49.2
55.4
64.0
73.2
70.6
60.8
49. 0j39.4
29.4
15
21.9
27.6
37.8
49.2
55.6
64.0
72.4
71.0
59.8
48. 9i37. 8
25. 5
26
Alpha ---
40.0
39.5
50.1
58.0
66.4
72.2
75.8
75.3
70.0
59.7
49.7
40.6
21
21.0
25. 6
35.4
45. 1
52.4
60.4
68. 1
65.8
56.8
45.7
34.2
23.0
10
Beattyville-
34.6
35.7
45.8
54.5
64.4
72.6
75.8
75.0
69.7
57.8
45.2
35.8
18
26. 8;33. 5
42.6
50.0
55.8
63. 6
71.4
69.6
60.6
49.0
39.2
30. 5
12
Blandville_
35.8
36. 2
48.4
57.2
66.8
74.8
78.1
76.8
71.0
59. 0
48.2
37.6
28
27. 2j30. 0
36.2
45.1
51.8
58.5
64.2
63.6
55.0
45.8
36. 6
30.8
20
Bowling Green—.
37.1
37.6
49.0
57.7
68.0i75.9
79.2
77.8
72.2
59.8
48.0
38.0
27
33.1137. 4
45.4
52.6
59.0
66.2
74.7
73.4
63.4
52.6
42.4
35.4
20
Earlington.....
35.4
35. 6
48.0
57.0
67.4|75. 6
78.6
70.8
71.4
59. 4
47.8
37.6
28
17.0120. 1
30.5
41.9
49.5
57.8
06.4
64.6
55.2
43.4
31. 2
19.4
13
Eubank_
34.8
34.8
46.2
54.4
64. Oj 71. 5
74.9
73.8
68.4
57.0
45. 1
36. 1
28
28.6 31.3
38.6
46.7
53.4
62.2
70.4
69.4
59.4
48.9
38.4
29.2
28
Irvington-
35.7
35.2
47.9
55.4
66. 4[ 74. 1
77.4
76.0
70.6
59.2
46.7
36.6
25
28. 6j34. 2
42.6
51.2
58.2
05.8
73.3
72.0
61.4
50.8
39.9
30.2
28
Lexington...
33.6
34.0
44.1
53.6
r>4.2
72.6
75.9
74.4
69.0
57.1
44. G
35.8
39
26.5i29.4
37.9
46.2
53.5
62.6
70.9
69.3
59.8
48.4
38.0
27.3
21
Loretto...—
36.4
34.6
47.2
55.2
65.6] 72. 6
76.2
75.6
69.9
58.2
46. 5
35. 7
20
34. 6 38. 0
42.7
.50.4
56.3
61.9
70.8
69. 8
60.2
52.0
42.0
35.6
15
Louisville.
34.7
36.4
46.0
56.2
06.6>| 74. 9
78.8
76.9
70.6
59.0
46.6
37. G
50
23. 4[26. 8
35.0
45.4
53.0
59.0
65.0
63.6
53.9
44.8
33.7
27.4
28
Maysville__
32.7
32.3
44.9
53.4
64.6172.9
77.1
75.6
69.6
57.6
44.8
34.1
24
28. 7132. 4
39.2
46.8
53.6
60.3
66.0
64.6
57.0
48.2
37.9
31.2
22
Middlesboro..
37.8
39.0
49.0
56.8
04. 7 72. 4
75.3
74.4
69.5
58.0
46.4
40.6
23
17.8|24.1
35.0
45.7
52.3
59.7
67.0
64.4
56.0
44.4
32.5
19.9
14
Scott..
32.4
31.7
44.2
53.0
04. 0171. 7
1
76.2
74.9
69.2
57.8
44.9
33.4
25
i University of Arizona.
30
AVERAGE MONTHLY TEMPERATURES AT SELECTED STATIONS—Continued.
(Monthly mean temperatures]
—
LOUISIANA
NEW
MEXICO
SOI
JTH
DAKO
TA
Stations
>>
fe
g
>1
fe
3
Q
©
u
i
1
>>
S3
t
©
a
a
d
3
3
<
(->
©
a
©
©
n
U<
5
s
§
»
a
£
>>
o
5
5 °
a x
B w
6 a
l 3
'dlo
© fe
© ©
Stations
>*
fe
d
d
cc
>>
3
3
5
©
a
3
£
1
>>
35
$
©
G
3
5
3
.-a
3
3
<
t-4
©
O
6
©
D.
©
n
u
©
5
$
3
a
©
>
0
£
© !*c
c X
3 tt
8 l
©
3
08 g
£>:
Stations
fe
3
d
>>
c3
d
(-1
£5
©
d
©
fe
s
- !
Q.
<5
a
%
©
d
a
“5
>>
d
>“5
§
fcD
d
<1
©
X
B
©
S
©
m
U.
©
d
O
©
O
a
©
>
0
fc
U. ‘c
©
-0 £
a t
8 §
©
P K
'd to
i—< »—»
* O 03
f © ©
© >4-
»-»W
Alexandria.
Amite...
Calhoun...
Cheneyville.
Grand Couteau.
Lake Charles.
9.2 5
51.4 5
17.0 4
50.2 5
53. 2 5
51.8 5
1. 1 5
5.2 6
5.4 5i
2.06
1.9 6
5. 7 6
1. 9 6
1.26
6.8 6
0.7 6
2. 3 61
0.9 6
1.8 7
3.9 7
1. 1 7
'.0 7
3.4 7
7. 2 7
1.6 81
3. 5 7'
1.7 7
3.6 7
4.2 7
3.6 8
i.i
1.8
1.0
3.9
0.9
0.0
32.18
31.2 8
31.3 8
31.7 8
31.7 8
31. 5 8
l. 9 7
1.2 7
0.8 7
1.4 7
1.3 7
1.5 7
7.16(
7. 16
5.3 ly
6.8 6
7.6 6
7.716!
5.3 5
5.6 5!
1.7 5
3. 4 5S
7.6 5
3.3 5
7.3 4
3. 15
1.9 4
3. 3 5!
3.5 5
3.6 5
1.6 5
6.0 4
3.6
1.6
7.2
3.5
3.9
2.8
5.3
8.9
31
31
31
31
34
31
48
47
Agricultural College-
Albuquerque-
Alma_
Chama.
Clayton..--
Clovis.
Corona.-
Cuervo_
Fort Bayard.
Fort Stanton--
Fort Sumner_
Fort Union......
42.3 4
15.2 4
38.0 4
23.4 2
35. 13
35. 6 4
5.3 5
9.3 4
1.5 4
5.1 3
7.6 4
0. 6 4
3.2 a
8. 0 5
6.9 5
2.2 4
3.4 5
6.4 5
0.7 6
5.4 6 .
3.3 a
2.0 4
1.5 6
4.9 6
1.3 7
1.7 7
3.7 6
3.6 5
3.0 6
5.3 7
3.3
10
3.3
3.2
9.6
3.6
30.5 7
76.0 7
74.1 7
53.2 6
73.4 7
78. 0 7
3.77
4.2 6
2.8 6
2. 6 5
2.6 6
5.8 7
2.3 6
7. 7 5
6.9 5
5.6 4
6.3 5
0. 1 5
3.0 5
9.8 5
6. 1 5
1.3 5
9. 1 5
8.7 4
2.0 5
9.5 4
0.9 5
9. 7
0.7 5
9. 8 5
1.0 5
1.6 4
6.2 4
5.8 4
6. 13
5.4 4
8.2 4
3.0 4
8.8 4
6.5 4
1 Q 4
3.4 4
4.0 3
5.6 3
5.8 2
4. 2 3
5.4 3
3.0 3
7.8 3
6.2 3
1 8 3
2.2
5.2
7.4
4.7
3.2
5.2
4.9
7.6
9.0
5 5
58
21
22
19
16
10
10
12
46
42
Aberdeen.-.
Academy.—.
Brookings__
Camp Crook_
Cottonwood-
Highmore.
9.91
19. 2 1
12.7 1
17.0 1
18.4 1
13. 4 1
11. 2 1
1.9 2
9.2 3
4.6 2
9. 1 2
9.13
5.4 2
3.7 2
7.3 4
3.6 4
9.5 4
8.3 4
4.7 4
9.0 4
9.0 4
4.6 5
7.4 5
4.5 5
3.6 5
6.8 5
5. 1 5
5.8 5
6.2 6
8.3 6
5.7 6
3.6 6
5.5 6
5.8 6
6.2 6
5.5
8.0
4.8
2.8
7.8
6.5
6.3
71.0 6
74.0 7
70.16
70.16
74.5 7
72.3 7
71.6 6
8.55
2. 1 6
8.4 5
8.4 5
1.0 6
0.4 6
9.6 6
9.54
3.2 5
9.7 4
8.3 4
1.7 4
2.2 4
0.8 4
6.0 3
1.2 3
7.3 3
5.3 3
8.0 3
8.3 3
7.7 3
0.01
6.8 2
1.81
1.6 2
4.5 2
3.6 1
1.41
5.1
2.9
7.7
1.6
0.9
8.8
8.8
7.1
0.7
S.8
0.0
2.3
5.0
25.
22
25
22
11
21
39
New Orleans...j
Shreveport.1-i
54. 3 5
17.151
6.8 6
0.3 5
3. 1 6
8.5 6
3.7 7
6. 0 7
5.2 8
3.3 8
0.8
0.4
32.3 8
32.9 8
2. 2 7
2.2 7
9. 01 /U. ft ft
6. 6166. 3 5
38.8 4
38.7 4
35.4 3
38.0 4
32. 2 3
32. 13
23.0 2
42.2 4
40. 1 4
38. 2 4
38.4 4
29.2 3
38. 1 4
29.9 3
26.5 3
1.6 4
0.7 4
8.4 4
2.2 4
3. 13
5.6 4
8.83
5.0 4
3.3 5
1.4 4
4.0 5
2.8 4
3.3 4
2.0 4
1.4 3
8.8 5
6. 1 5
3.7 5
9.2 5
9.2 4
0.6 4
6. 6 4
8.4 5
1.4 5
8.6 5
1.4 5
0.0 4
9.5 5
1.6 4
9.6 4
5.8 6
2.8 6
0.9 5
5.8 6
5.2 5
7.8 5
2.6 5
9.5 6
8.3 6
5.9 6
8.4 6
6.9 5
7.0 6
9. 6 5
6.1 7
1.2 7
8.7 6
5.8 7
3.2 6
5.2 6
2.8 6
7.0 7
6.5 7
4.8 7
5.9 7
5.4 6
5. 1 7
8. 7 6
4.4
0.8
7.0
4.4
2.0
5.4
3.2
5.6
5.2
4.0
4.7
4.9
4.6
7.1
2.9
78.8 7
72. 4 7
69.0 6
77.9 7
65.9 6
69.6 6
68. 6 6
77.8 7
77.7 7
78.4 7
77. 8 7
68. 6 6
76.9 7
70.6 6
68. 0 6
5.8 6
0.9 6
Milbank_
Mitchell.-.
Oelrichs.-.
Ottumwa__
Pierre--
10. 7 1
16.01
21.5 2
2. 7 2
6.9 3
2.6 3
7.8 4
1.7 4
3. 2 4
3.6 5
6.4 5
5.4 5
5.5 6
7.7 6
5.0 6
4.6
6.9
5.5
70. 1 6
72.16
72.3 7
8. 1 5
9.8 6
0.3 6
9. 6 4
1.54
0.8 4
7. 2 3
9.4 3
7.7 3
1.1 1
4.4 2
4.6 2
3.6 2
4.22
0. 2 1
2^
25
23
12
29
11
MAINE
6.8 6
5.0 5
8.3 6
6.8 5
6.9 7
6.3 6
6.8 7
6.9 6
7.4 6
5.2 6
9.4 6
6.7 6
6.9 4
9.0 4
6. 4 3
0.4 3
7.2
1.2
11
23
16.0 1
17.1 1
7.6 1
7.7 3
8.2 3
2.2 2
1.2 4
1.8 4
7.6 4
4. 7 5
7.4 5
4.4 5
4.0 6
8. 1 6
4.2 6
7.0
8.6
5.0
72.8 6
74.9 7
70.9 6
9. 6 6
3.0 6
8.3 5
O. 4 4
3.7 5
8.6 4
7.5 3
0.4 3
4.9 3
Eastport.
Greenville..
Portland.
Presque Isle.
20. 5 2
12.8 1
22.4 2
10. 5 1
1.02
2.4 2
3. 3 3
1.02
1
9.2 3
3. 5 3
2.2 4
4. 5|4
1
8.8 4
6. 4 4
.3.6 5
0.2 5
7.5 5
9. 5 5
4.4 6
1. 4 5
5.0
8.9
3.7
7.3
60.4 6
65.4 6
69.8 6
64.2 6
0.6 5
2.5 5
7.8 6
4.6 5
I
5.8 4
5.0 4
1.0 5
3.6 4
7. 5136. 9 2
5. 6!30. 7 1
0. 7 39. 0 2
5.8|28.2 1
1
5.4
8.0
7.8
6.4
47
15
46
11
Fort Wingate..
Haynes.....
Lovington....
Roswell...-
San Jon.....
San Marcial.-
Santa Fe.....
Socorro....
Springer.
8.2 3
9.5 4
7.9 4
9.2 4
7.7 4
0. 2 3
6.7 2
8.5 4
7.2 3
7.2 3
6.8 3
9.0 3
3,6
0.8
8.5
7. 1
6.9
0.4
9
13
27
15
25
48
Rapid City.-.
Rosebud..
Sioux Fails_
Vale..-
Yankton.--
22.8 2
22.8 2
15. 1 1
18.7 2
16.91
2.5 3
2. 1 3
6.5 3
1.0 3
9.8 3
2. 1 4
2.5 4
1.3 4
3.0 4
2.4 4
5.2 5
7.0 5
6.2 5
6. 2 5
7.9 5
3.7 6
6.8 6
8.0 6
4.2 6
9.4 6
4. 1
6.5
7.2
5. 1
8.9
70.9 6
73.4 7
72.3 7
71.7 6
74.17
9.6 6
1.0 6
0.5 6
8. 8£
2.2 6
0.7 4
1.14
1.9 4
9.9 4
3. 4 £
8.4 3
9.0 3
9.4 3
6.8 3
1.0 3
6.0 2
6.4 2
3.5
4.2 2
4.9 2
7. 7
4.0
9.7
21.
22. 9
33
20
25
13
48
MARYLAND
8.6 5
2.4 5
0.0 4
7.2 4
1.0 3
9.0 3
6.2 3
9.7 2
8.2 2
7.0
9.8
6.4
26
23
23
TENNESSEE
Baltimore.
Cumberland.
Frederick.-------
Princess Anne .-
Washington, D. C.
34.2 3
31.0 3
32.1 3
37.0 3
33.7 3
4.9 4
2. 7 C
2.6 4
6.7 4
4. 7
2.4 5
9.5 5
1. 9 5
5.5 5
2.6 5
3.4 6
1.8 6
2.6 6
►4. 4 6
3.4 6
4.3 7
2.8 7
3.5 7
3.2 7
A. 2 7
2.7
0.3
1.7
1.1
2.4
77.4 7
73.9 7
76.2 7
76.2 7
76.8 7
5.3 6
2.0 6
3.9 6
4. 7 f
4. 7 e
8.6 5
5.0 5
7.15
>8.7 5
>8.0 5
7.8 4
4.3 4
5.7 4
7.8 4
6.9 4
6.1 3
2.3 3
3.9 3
7.3 3
5.2 3
6.8
3.7
4. 5
8.8
6.1
50
37
46
45
50
Taos..-..
/. 1 DO. 1 O
Carthage..
Chattanooga...
Johnson City....
Johnsonville_
38.4 4
41.4 4
37.13
39.6 4
38.7 4
0. 4 4
9. 7 5
8.9 6
7.4 7
5. 1
77.6 7
6.9 7
1.6 6
>0.1
8. 7
0.0
37
NEW YORK
3. 5 £
8.3 4
0.1
1. 2 4
1. 6 £
7. 8 £
1.3
9.0:
>0.2 6
5.4 6
9.2 6
8.0C
8.6 7
>5.2 7
8.4 7
6.9 7
5.6
2.0
5.5
4.0
78.2 7
75.0 7
78.9 7
77.0 7
7.4 7
3.9 6
8.3-
5.9'
2.16
8. 6£
2.3 6
0. 4f
3.4 6
1.7 6
1. 6£
7.7 4
>0.8 4
9. 1
>3. 0 £
>0.6 4
> 0 . 81
5 . 8 ;
9 . 3 ;
7 . 7 ;
1. 6'
8.9'
2.6
7.9
9.9
9.8
13.6
11.0
42.
25
25
50
50
50
4.2:
1.5;
2 . 8 :
3.71
5.61
>0.2
13. 4
10. 5
>2. 9
11.7'
27.0'
28.3-
6 . 7 ;
3.2
15 . 2 ;
12 . 5 ;
12 . 6 .
11 . 3 .
9. 1C
4. 3f
6. 8 f
4. 2 (
4. 5
4. 4
8.2
3.4
5.3
4.6
3.9
>3.6
72.3 7
67. 5
69. 8
69. 8 f
68. 6
68. Of
0. 4f
5.0;
7. 7 f
8. 6 f
6. 1
5 . 5 ;
2. 6£
8. 7 4
1. 4
2. 5 £
8.6 4
8.4 4
0.6 3
7. 5 3
>0.4 3
1.5 3
7.2 3
7.0;
9.2 2
6.2 2
8.4 2
9.2 2
4.5 2
5. 12
8.0
6.2
7.7
99
35
30
Memphis..
41.0 4
38.8 4
36. 2 a
40.7 4
38.3 4
38.61
3. 6 £
0.9 4
6.9 4
2.6
0.4 4
9.7 4
2. 6f
9.6£
6.4£
1.9
9.8f
9.6,
1.8 7
9. Of
4. 8 f
0. 5f
9. 6 f
7. 8
0. 4
8.2'
4.1
>8.8'
8.0
6.0
1.2
5.9
80.8 7
79.1
74.1
79.0 7
9. 6
8. 0
MASSACHUSETTS
Albany.
Angelica...
Binghamton-
23.15
24. 1
Nashville_
Rugby....-
Savannah-
3. Of
8.5'
7 4
>7. 4
2. 3 f
n s
5.7 4
>1.0.
9 7
5.0;
0.2
8.3;
17.3
12. 1
19. 6
33
34
38
Boston..
Nantucket.
Williamstown.._
27. 9
31. 9
22. 5
7.8,
10.2
11.4
15.7 4
16. 0J
12. 3
6.0 c
3.7.
3.9,
7. If
2. 6 (
>5. 6
6.3
>0.9
>3.5
72. Of
67. 7
68. 6
9. 9
7. 6
>6.2
53.4
>2.9;
59.2 4
3.3 4
4.2 4
9.6 3
1.9131.9
4. 7 35. 8
7.1 25.8
49
34
Buffalo...
Canton..
Cooperstown.-.-
Indian Lake--
Ithaca--
New York City__
Oswego-
Rochester...
25. 0 5
16.0
20. 4
1.5
4.8
23
65
Trenton--
Tullahoma...--
>6. 1
3.1
76.3'
5.6'
> 0 . 2 :
>8.7'
17.4
10.0
32
18
16. 1
24 . 5 ;
30.8,
23.81
24.6
23.8
29.7
5.0
!4. 1
10.7
13.5
23.6
21.7
27.7
26.5
32. 1
18.0
30.8
31.8
32.6
36. 1
18.9,
14.8.
18. 8
12.5,
14.4
14.0
48.0
>1.8.
>7. 2
>0.0(
>3. 5
>6.6
>9.7
>6.0
>9.0
>2.9
>6.0
65. If
70. 7
74.3'
69. Of
20. 9
2 . 4 :
8. 2 f
2. 7f
>7. 8
>8. 8
6.2 4
1.8,
6.6,
>1.2,
>2.6,
5.8 3
>0.7;
>6. 1
>0.21
>1. 1
2.2 2
8.8 2
4.4;
18. 9 2
18 . 8 :
(S 4
0.1
8.7
4 2
21
42
49
TEXAS
MICHIGAN
>8.3
>8.7
>7 9,
65
49
18
Abilene..
44. 5
56. 2
16. 8
)8. 2
>6.2
34.5
>4.3'
71. 1
1.8'
77. 4
19. 2
12.7
82.6>
84. 6
12.0
15.7
75. 4
11.2
55. 2
13. 4
>3.9
>4.0
15.9
57.3
35
11
Alpena..-.
Big Rapids.
Cheboygan---
Detroit.-.
Escanaba.
Ewen.
Grand Haven-
Kalamazoo.
Lansing—--
Marquette_
Omer_
Sault Ste. Marie.
Traverse City-
18.8
20.2
17.7
24.0
15. 1
10.8
17. 4
8.3
15. 5
24.5
14.6
10.7
25. 5
29. 8
25.8
33.6
24.3
23.4
18.8,
13.8
10.3
15.9
37.9
38.7
>0.2<
55.01
50.81
57.7
19.0
50. 5
>0.4
54.4
>1.9
>7.2
30.5
>0.4
65. 9 e
69.0*
53.9
56. 4
57.8*1
59.4*1
i7. o:
is. o;
S4.7;
i5. 9
>4.7
35. 0
46
27
Syracuse--
West Point.
>9.4
>8.6
73! 2
7L 3
> • ®
>4. lj
>2.9
11. 5
10.9
86
Amarillo--
Big Spring-
36.4
45.7
48.8
51.4
59.4
46.8
39.9
44.3
56.2
33.4
45. 1
52.4
44. 7
55.9
59. 1
15.4
18.2
19.0
53.7
52.9
18.4
42.6
46. 5
58.1
35.4
47.4
55.6
49. 5
58.8
61.7
17.0
57.1
>5. 2<
34. 4!
>5.6'
73.1
12. 7
11.0
74.9
83.2!
5.4
13.1
12.8
13.9
13.9
13.7
10.8
36.2
76.2
77.1
79. 1
10.5
76.9
74.5
>7.6
>5.2
>6.9
16.4
>3.6
>6. 6
16. 6
14.2
18.4
29
19
22.
67. 0
72.2
66.0
65.0
>5.0
’0.2
34.0
31.3
59. 2
53.6
57.2
54.8
17. 9
> 2 . i;
16. 2
14.6
34.71
39. i;
33. 6
30.6
23.7
29. 1
23.6
16.4
30
50
38
22
NORTH
CAROLINA
Blanco--
Brenham-
Brownsville_
Brownwood_
Childress--
Clayton ville.--
Corpus Christi-
Dalhart___
Dallas--
Del Rio.--
El Paso_
Encinal..
Falfurrias_
52.2
68.3
56.7
53.0
JO. 4
■». 4
7 3. 7
55. 1
61. 8
74.9
78.6
72.4
>9.0
11.3
12.4
10.7
78.0
83.9
83.8
83.9
81.8
39.9
'4.6
35.8
33.4
>0.7
37.5
54. 1
19.7
12.3
51.5
16.3
13.6
37
60
27
14
24.2
23.3
21.9
16.6
19.0
14.0
22. 1
23.5
23.3
22. 1
16.4
16.9
11.9
19. 2
31.6
34.2
31.0
24.7
28.7
22.0
29.5
13. 7
16. 7
45.6
38.2
42.0
37.7
41. 5
54. 1
57.8
57.6
49.0
52.9
48.8
52. 1
33.7
37.6
36.9
58.8
63.7
58.7
63.0
68.7
72.3
71.0
65.4
68.2
63.3
69.1
37.0
70. 1
68. 5
53.6
65.7
62.0
67.4
61.0
63. 1
61.2
57.5
59.7
55.8
60.8
>0.3
51.1
19.5
46.7
49.4
44.9
50.2
38.4
38.0
36.3
33.0
36.3
32.4
37.7
29.4
27.3
26.0
23.0
24.6
20.8
27.6
48
45
57
47
24
33
27
Asheville...-
Brewers--
Charlotte.-
Edenton-
Greensboro--
Hatteras--
Lenoir.--
38.2
38.4
41. 5
42.6
40. 1
46.0
37.3
38.0
38. 7
43. 5
42.2
40.8
45. 9
41. 1
47.1*
47.7
51. 3
50. 9
49.7
50.0
46.9
54.0
55. 1
59.0
58.5
58.0
56. 5
56.2
62.7
64.6
>9.0
68.4
68.0
65.8
64.9
68.9
71. 6
75. 7
74.8
74.8
74.2
71.8
77. 1
76.0
75.3
71.9
74. 9
78.4
79.2
77.8
78.0
75. 1
80. 1
79.0
78.3
71.4
74. 1
76.9
78.4
76.6
78.0
73.8
79.2
78.3
77.2
66.0
68.9
71.8
71.8
70.7
75.8
67. A
73.4
72.7
71.5
56. 1
59.0
61.2
61.5
60.4
66.8
57. 1
45.8
47.7
50.8
50.9
48.6
57.2
46.4
38.0
39.2
42.9
42.8
40. 5
49. 1
38.7
18
26
44
24
38
44
47
54.3
64.4
45.3
56.4
63.7
55.9
65. 1
67.9
53.6
70.5
52.3
64.7
69. 5
63.5
72.0
73.7
71.2
75.8
51.8
72.7
76.6
71.9
79.9
78.7
78.8
80.5
71.8
80.7
82.8
80.3
85. 2
83. 5
81.7
82.0
76.6
84.0
84. 5
81.6
86.6
85.3
81.5
81.2
83.4
31.1
12.3
74.6
33.3
34. 6
79.6
86.8
85.9
80.4
79.8
83.2
75. 4
79. 7
68.0
77.3
79.5
73.9
81.6
81.8
74. 5
73.9
79.9
35.3
73. 1
55.2
66.2
69. 5
53.7
73.4
74.4
65.7
64.9
72.5
53. 1
54. 0
43.2
54.9
59. 1
52.3
63.6
66.0
14.3
57.7
32.0
46.7
51. 1
45. 1
5-1.8
58.6
23
34
13
44
15
41
10 !
14
MINNESOTA
Lumberton--
New Bern--
Raleigh-
44.2
45.7
41. 7
43. 6
46.0
42.5
53. 6
53. 5
50. 6
61. 6
60.0
58.9
70. 8
69.4
68.5
63.2
60.8
53.8
50.7
46.2
42.6
33
34
29
47
50
Fort McKavctt.....
Fort Stockton-
Galveston_
Graham-
Hallettsville-
44.4
46.5
53.6
50.5
50.5
55.9
58. 1
57.9
62.5
65.4
64.7
69.2
72. 7
73.5
75. 5
78.4
79.9
81.3
54. 1
63.0
53.8
61.9
53.3
46.4
56.3
45.9
54. 1
44.2
33
49
22
29
26
32
38
29
16
37
Alexandria.
Bird Island-
College ville..-.
Duluth---
Fairmont...
International Falls_
Montevideo....
6.8
11.1
9.4
13.3
25.4
28.6
42.3
44.6
54.6
56.7
64.5
65.6
69.5
71.0
67.0
68.6
58.4
61.0
46.2
47.8
29.6
31.4
13.5
17.3
27
31
Southern Pines.
Weldon...
Wilmington...
44.0
39.7
47. 1
44.3
41.1
48.3
53.6
48.4
54.6
61.3
57.5
61.4
70.4
68.2
70.0
76.9
75.4
76.4
78.9
79.2
79. 6
78. 5
77. 3
78.7
73.3
71.2
73.8
62. 8
59.5
64.4
QZ. Oi*i*i. O
48. 4140. 6
54. 9 48. 0
44. 1
53.7
43.4
46.3
55.0
45.3
58.0
63.4
55.0
65.5
69.8
64.2
73. 1
76. 3
72.0
80.9
82.2
80.8
84.6
84. e!
84.4|
83.7
84.4
83.6
77. 2 60 . 8
79. 9170. 9
70. 8165. 3
11.7
14.1
28.3
44. 6
56.0
65.7
70.8
68.1
60.0
47.6
31.6
17.6
28
Houston.---
Huntsville-
Lampasas_
Liberty-
Longview_
53.2
55. 1
62.9
69.3
75.1
81.1
83.3]82.9
83. 5(83.0
83. 0*83.1
83.0jS2. 7
83.9 81.1
78. 8170. 4
77. 6l68. 2
76. 8|66. 5
79. l|69. 5
77. 2 66.3
61. 2
58.7
56. 1
61.4
56. 1
57. 1
47.9
52. 6
57.3
53.9
57.6
61.8
60. 2
60.8
54. 1
58.8
60.3
63.8
54.7
54. 2
50.9
48.3
53.8
48.0
47.5
37.0
43.3
48.0
47.0
50.4
54. 2
40.6
53.8
45.8
49.6
52.9
55.8
45. 2
9.3
13.2
2.5
11.4
12.4
15.8
6.2
13.6
23.8
30.4
20.4
28.4
38.0
45.6
39.4
45.4
40.2
40.6
40.0
46.2
44.3
48.1
57.0
51.4
57.0
52.1
52.8
52.0
57.6
55.9
58.4
66.6
02.2
66.4
63.0
62.8
61.2
67.2
65.0
65.4
71.6
66.6
71.2
67.7
68.3
65.4
72.0
70.2
63.8
69.6
62.9
68.7
56.3
61.3
55.6
61.2
45. 0
49.2
42.4
48.1
43.0
45.2
41.4
48.6
47.6
29.6
32.8
25.6
32.0
26.6
29.4
23.9
32.3
32.0
16.9
20.0
9.9
17.6
11.4
12.3
7.6
19.4
18.8
47
30
17
30
29
24
16
46
26
NORTH DAKOTA
49.3
47.6
55.0
47.4
51.0
49.0
55.8
49.4
59.8
58.5
62. 5
57.8
67.3
65. 1
68.0
65.1
74.0
72.4
74.0
73.7
80.8
79. 7
80.9
81.3
80. 1
76.0
78.3
79.0
78.3
79.4
Park Rapids....
Pine River Dam..
Roseau .—-
St. Paul..
Worthington_
3.7
5.4
-0.4
12.3
13.0
6. 4
7.1
2.0
16.2
14.6
22.4
23.8
20.1
29.3
28.9
65.6 57.1
62.R54.2
69. 5 61.0
68.3 60.2
Bismarck.
Bottineau...
Crosby. ....
Devils Lake..
6.7
-0.7
1.7
2.9
10.3
6.5
3.6
6 5
9.7
1.8
7.1
4.2
11 8
23.6
17.7
22.0
19.8
24.4
43.1
39.4
40.6
40.1
42.9
54.1
51.3
50.4
52.0
52.2
63.5
61.0
60.6
61.7
61.3
69.5
65.8
65.9
67.1
68.0
67.4
63.6
63.7
64.7
66.3
57.6
55. 5
53.7
55.9
56.5
44.8
41.6
41.5
43.0
43.9
27.9
23.6
27.8
26.8
28.6
14.9
6.7
12.3
9.4
17.3
43
26
11
21
26
Mexia..
Miami_
Midland_
Nacogdoches-
02 Ranch_
Palestine..
47. 1
38.0
42.5
47.9
47.2
47.9
48.9
40.7
47. 2
50.9
52.3
50.9
58.3
49.7
54.8
59.0
55.6
59.0
64. 7
57.9
64.5
64.7
63.2
65. 9
71. 8
66. 6
72.2
71.8
72.3
72.2
0
80.3
81.6
81. 5
79.5
82.0
78.8
79.5
81.7
76.9
81.8
72.2
73.9
76.6
71.9
76.9
77.9
70.6
79.0
59.2
64.3
66.4
64. 5
67.4
69.8
60.6
70.3
65.6
68. 1
71. 1
72. 5
65.4
15
14
21
7
39
15
25
36
MISSISSIPPI
Garrison...
Grand Forks..-
8.4
6.5
7 9
21.7
22.4
22.6
19.2
23.1
21.4
26.6
24.1
16 0
42.6
42.0
42.5
52.6
53.4
53. 5
62.2
62.9
63.1
68.1
67.4
68.5
65.7
64.9
66.2
56.8
56.2
56.7
43.8
43.5
44.8
27.0
26.1
27.6
13.6
10.6
13.6
23
25
26
Pierce... . .---
Plain view___
San Antonio. -
54.5
41.0
42. 7
54. 7
42.2
55.2
62.0
51.0
62.6
67.3
59.0
69.1
73. 7
67.6
75.0
79. 5
74.8
81. 1
81. 8
77.3
83.5
82. 4
76.8
83.6
Bay St. Louis.
Booneville..
Brookhaven..
Duckhill..
Hattiesburg--
Holly Springs..
Lake__
Louisville.
Meridian..
Natchez.-...
Vicksburg-..
52.0
41.6
48.5
45.0
49.7
53.7
42.8
50.6
46.2
51.7
62.0
52.5
59.1
55.8
60.4
67.4
60.6
65.5
62.4
65.6
74.6
69.0
72.9
70.3
73.4
80.3
76.9
79.6
77.0
80.4
81.3
79.4
81.5
79.7
81.9
81.6
78.8
81.1
79.4
81.6
79.0
73.6
76.6
74.3
77.1
69.4
62.2
66.1
63.3
60.1
60.0
51.2
56.5
53.3
57.2
52.5
42.2
49.4
45.2
50.3
28
25
33
22
28
McKinney..
Manfred..
Minot...
Mott..
Oakdale.....
Pembina..
Williston...
3.2
4.0
5.0
7.5
14.4
= 2.9
5.8
5.1
6.8
7.9
11.8
13.3
1.4
7.9
41.0
41.8
41.7
42.6
42.8
37. 9
52.0
51.6
52.3
51.6
53.3
52.5
60.7
61.5
62.5
63.0
61.9
62.6
66.0
66.9
68.1
69.1
68.0
67.7
63.5
64.3
65.1
65.9
66.6
64.1
54.1
55.9
56.7
56.3
57.1
53.8
41.7
43.3
43.6
43.0
45.6
40.9
24.6
29.0
29.7
31.2
28.4
22.7
10.7
11.3
12.4
14.1
20.5
6.0
25
15
19
11
15
38
Sherman__
Taylor--
U valde---
Victoria_
Weatherford__
43.6
49.4
53. 1
55.9
43.9
46.6
51.2
56.6
57. 1
45.5
55.5
60.4
64.5
64.7
55.9
63.8
66.4
70. 1
70.6
64.0
71.6
73.2
76.6
76. 2
71.5
79.6
80.4
82.6
81.9
79.8
82.8
82.9
84.9
84. 1
83.8
82. 2
83.0
84. 1
84.4
82.4
76. 1
78.0
79. 1
80.4
76.1
19
17
21
32
39.9
56.7
46.0
47.2
49.9
48.2
40.6
47.9
47.2
48.7
51.5
51.3
51.7
57.0
56.1
57.1
60.4
58.7
60.0
63.8
62.7
64.2
66.7
65.6
69.3
71.0
70.4
71.5
73.4
72.8
77.4
77.9
77.7
78.1
79.6
79.3
79.9
79.9
79.4
79.7
81.6
81.3
79.2
79.3
79.8
79.5
81.6
80.9
74.0
74.7
75.2
74.9
77.4
76.2
62.3
63.2
64. 6
64.3
67.1
66.5
50. 5
53.6
54.4
54.6
57.9
56.6
40, 6
46.8
46.6
47.3
49.9
49.8
30
33
30
22.7
43.0
53.3
63.1
68.5
66. 5
56.0
43.6
27.0
13.6
39
UTAH
31
33
49
OHIO
Castle Dale...
Fort Duchesne--
Hite_
19.3
13.0
35.7
25.8
19.3
42.4
37.8
36.0
51. 1
45.9
47.8
59.2
53.9
55.7
68.2
63.8
64.8
77.7
68.0
58.6
63.4
72. 1
64.3
67. 1
62.9
69.3
71.0
84.2
75.6
65.9
71.7
77.7
70.5
75.6
69.2
68.1
69.3
82.8
73.0
62.9
70.7
75.3
66.6
74.5
68.3
58.9
60.5
72.5
60.2
53.0
61.2
66.3
60.2
64. 4
59.3
47.8
46.8
59.7
47. 5
41.3
49.9
53.6
49.4
52.5
47.9
36.8
33.7
47.5
34.3
31. 1
37.7
23. 1
17.5
35.2
26.3
20.9
25.7
19
29
14
39
18
27
28
28
• 45
24
M
ISSOURI
Cincinnati.
Circleville..-
32.4
30.9
33.9
29.9
26.6
30.0
28.0
25.0
29.2
43.1
42.4
35.0
39.9
39.1
37.8
38.0
53.7
52.1
46.2
51.0
49.9
47.0
50.7
64.4
62.9
57.9
62.2
60.9
58.0
61.3
73.1
71.2
67.1
70.9
69.6
65.2
69.5
77.2
75.4
71.8
75.1
73.6
70.7
73.7
75.3
73.5
70.0
72.8
71.3
68.9
71.2
74.3
71.9
71.0
68.8
67.6
64.1
66.6
64.5
62.6
64.8
67.9
65.3
64.7
57.0
55.6
53.2
54.9
52.9
51.9
52.1
55.9
53.6
53.1
44.5
43.0
40.6
42.0
40.9
39.1
39.7
44.8
40.8
40.0
35.3
32.5
30.8
32.2
30.7
28.4
29.9
36.5
30.7
30.2
48
27
Kelton..
Loa...
Logan--
Moab--
Parowan_
Salt Lake City--
Scipio.-.-
22.5
24.6
24.3
28.1
24.1
26.7
39. 2
32.2
36.2
43.4
39.4
41.7
38.7
48.3
10.6
47.5
55.2
47.1
49.9
46.6
57.4
48.7
54.4
63.6
54.6
57.4
53.1
Arcadia...— —
Bethany...
Brunswick...
Clinton_
Columbia...
Hannibal..
32.1
24.6
26.8
31.4
30.0
27.7
33.5
27. C
29.1
31. t
31. (
28.4
44.8
40.0
41.9
44.3
43. 5
42.3
55.3
51.2
54.1
55. 7
64.6
62.6
64.3
65.2
72.0
72.4
73.2
73.4
75.9
76.0
75.7
77.5
74.5
74.9
73.8
76.8
67.6
67.0
66. 7
70.2
56.1
54.7
55.2
58.6
44.0
42.9
41.5
47.3
34.3
30.3
30.6
34.4
40
31
42
28
Cleveland..-.
Columbus...
Greenville_
Millport--—
North Lewisburg-
26.9
29.1
27.6
26.4
27.4
43
35
25
77
91
53
48
28. 8
29.0
29.2
27.2
36. 2
31.9
33.3
31.1
40.6
40.9
37.5
28.8
32. 1
26.6
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53.3
54.9
55.7
55.0
55.8
56.1
50.7
64.4
63.9
64.6
65.6
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73.0
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77.0
76.9
78.2
76.9
77.4
76.0
75.4
76.8
76.3
75.8
68.9
68.2
69.4
69.5
68. 0
57.3
56.5
58.1
58.0
55.9
44.2
42.9
44.6
46.0
44.9
33.3
31.1
33.3
35.0
33.6
33
31
34
34
21
Portsmouth-
Sandusky..—.
Toledo.-.
Wooster....
34.7
26.9
26.2
26.5
36.7
27.1
26. C
26.2
45.0
35.5
35.8
36.7
55. 5
40.8
47. 5
64. 9
59.1
59.2
72.6
69.0
68.7
76.6
73.6
73.4
VERMONT
Kansas City.....
Lebanon..
Rolla____
St. Louis.....
Springfield...
Unionville.
29.7
33.0
31.3
30.8
33.6
23.5
30.8
33. £
35.2
34.5
33.'
25.4
43.2
45.4
45. C
43.8
44.8
38.6
47.9
58.5
67.6
71.5
69.5
63.6
51.6
40.0
30.1
36
Burlington--
18.9
18.8
29.9
26.8
26.2
28.8
43.2
41. 5
39.8
41.6
56.2
54.1
52.4
54.5
64.9
62.2
60.9
62.8
70.0
68.1
65.7
68.6
67.6
64.9
62.8
65.6
60.2
57.8
55.8
58.7
49.5
47.5
45.2
47.2
36.3
23.5
35
20
66.9
64.6
62.4
74.8
72.6
71.8
78.6
76.3
76.6
77.3
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75. C
70.1
69.5
67.2
58.4
58.0
55.4
45.1
46.2
40.2
34.8
36.2
27.4
41
33
30
OKLAHOMA
Enosburg Falls.
N orthfield_
Wells_
15. 2
15.2
18.3
15.0
15.7
17. 1
32.7
33.8
20.0
21.3
34
20
MONTANA
Ada..
41.3
43.0
53.2
60.2
68.3
76.4
82.3
81.2
74.7
62.2
53.0
41.7
36.8
42.4
40.1
34.2
38.7
36.4
45.0
42.8
40.8
40.7
36.7
14
20
20
22
25
20
23
9
19
28
20
24
VIRGINIA
Alva...
34. 8
36.6
48.2
58.0
66.9
76.4
81.0
80.1
72.6
59. 6
48. 2
29
25
48
50
40
17
Augusta__
Billings.....
Como__
Crow Agency...
Cut Bank....
Fort Benton..
20.8
22.
26.
18. t
14.
20.
22.3129. 2141.
25.0|34.2:47.
129.1:37.2 45.4
20.2|32. 6 46.
16.8129.242.
21.2130. 6145.
48.
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70T
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45.4
32.3
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30. C
33.2
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26. f
24.5
23. C
26. C
20.5
20.4
25. C
21
26
13
37
12
16
24
40
42
Ardmore......
Bacone--—
Beaver..
Chandler___
Enid..
Idabel.
McAlester--
41.9
38.9
33.2
37.2
35.9
44.5
41.0
40.0
39.6
35.3
43. 6
40.3
33.7
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43.
42.
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54.8
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51. €
49. £
55. £
54.
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53.
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62.0
60.4
57.3
60. 1
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61.6
61.4
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69.9
68.3
66.6
68.4
66.9
69.5
69.6
69.6
68.4
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78.9
76.8
75.7
77.6
76.8
79.7
78.5
78.0
77.0
77.1
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80.7
80.9
82.4
81.8
82.3
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82. 5
81.1
82.0
83.3
81.1
80.2
81.6
81.4
80.7
82.0
81.9
81.8
81.7
76.1
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71.3
74.0
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76.6
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64. 3
62.9
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52.3
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50.5
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52.3
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49.6
49.7
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50.1
49. f
48.4
Callaville_
Charlottesville—.
Lynchburg-
Norfolk_
Richmond_
W ytheville_
39.0
36.2
37.2
41.2
38.4
34.4
38.3
35.2
38.5
41.8
39.9
34.
48.5
46.1
46.4
48.2
47.2
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56.4
55.7
55.8
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66.3
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60.8
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77.2
78.6
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76.0
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71.8
70.9
64.2
59.6
58.3
57.9
61.8
59.9
53.9
48.6
46.0
46.9
51.3
48.9
42.7
40.0
37.5
39.2
42.9
40.3
34.0
Fort Logan.
Havre.
Helena..
Jordan___
Kalispell....
Malta...
Miles City.
Missoula..
Poplar..
Red Lodge..
Springbrook..
Valentine..
I 18.
12.
20.;
13.;
22.
10.
is.;
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6.
20. 6 27.
13. 2i27.
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12.6125.
16.9 31.
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151.4
Mangum...-.
Marlow___
WASHINGTON
42.
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143.;
51.
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43.6
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32.7
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33.1
27.7
18.3
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15.3
21.
24. €
14.7
11
25
15
44
29
36
Oklahoma City....
Tulsa__
Vinita-
Weatherford..
Woodward.....
37.1
36.5
36.
36. £
35.5
38.5
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38.1
39.5
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50.
51.
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61.6
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16
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20
Aberdeen.
Blaine...-..
Centralia_
Moxee.
North Head.
39.1
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38.'
28.:
41.
41.
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40.'
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30.6
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14
C
1REGON
Odessa_*-.
Republic__
Seattle.-.
Spokane .
26.
22.
40.
27.
32.
25.
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31.
141.'
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41.
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36
28
NEBRASKA
Albany-..
Ashland_
Astoria.-.---
Walla Walla.
Waterville__
33.
20.
37.
7 25.
Atkinson..
Curtis...
Fort Robinson...
Halsey.
Hartington-
Kennedy...
Kimball.—:.
Lincoln....-.
Madison....
Minden..
North Platte..
Omaha..
Scotts Bluff—-.
19.;
26.;
23.
22.'
18.'
23.1
26.1
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21.
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24
Baker_—.
Bend—..
Day ville..
Diamond__—
Eugene...
Joseph..
Klamath Falls--
Lakeview..
Newport..
Portland...
Riverside...
Roseburg....
25.
30.
34.
29.
40.
23.
28.
27.
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26
WEST VIRGINIA
2 33.,
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30
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Elkins.
Glen ville...
Huntington..
Parkersburg..
Powellton,...
31.
33.
32.
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27
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153.
7 36.
46.
127.
5 41.
20
1 45
1 24
2 60
2 26
Union...
32.
3 50.
5 60.
8 67.
3 71.
3 70.
5 65.
54.
41.
1
0 31.
) 17
3 37.
0 35.
3 51.
3 46.
2 62.
155.
3 71.
66.
6 76.
3 72.
5 74.
2 71.
6 66.
1 61.
54.
3 49.
139.
136.
0 27.
8 28.
47
30
2 32
Silver Lake...
The Dalles_
- 27.
_ 32.
9 31.
3 37.
5 31.
8 34.
1 35.
8 45.
7 41.
4 41.
8 42.
7 53.
1 49.
4 49.
4 49.
2 60.
5 56.
0 54.
55.
66.
6 64.
8 61.
9 63.
3 72.
71.
3 62.
2 71.
69.
3 53.
2 62.
59.
2 44.
53.
6 48.
3 36.
2 42.
5 37.
32.
3 35.
2 28.
WISCONSIN
Valentine__
Weston—...
- 31.
1 69.
68.
4 59.
2 50.
0 40.
9 33.
9 30
Barron —-....
. 9.
4 11.
5 26.
2 42.7 53.
4 63.
6 68.
3 64.
9 57.
9 45.
0 30.
0 16.
3 29
NEVADA
PE
NN
3YL
VANIA
Eau Claire..
Green Bay--
Hayward...
La Crosse.
. 12.
. 15.
614.
4 16.
7 29.
5 28.
7 ns
7 45.
7 45.
0 42.
7 47.
9157.
0 54.
153.
4 59.
2 66.
6 65.
1 63.
168.
7 71.
3 70.
3 67.
2 72.
1 68.
167.
4 64
8 60.
6 60.
4 57.
1 61.
8 48.
6 48.
3 45.
8 50.
8 32.
7 34.
4 29.
134.
6 18.
3 22.
7 16.
7 22.
9 30
3 34
2 31
27.
25.
27.
30.
43.
43.
26.
3 30.
127.
130.
3 35.
47.
149.
3 29.
6 35.
133.
136.
6 42.
0 53.
2 55.
6 35.
3 44.
3 41.
3 45.
150.
2 62.
5 63.
7 45.
2 50.
149.
2 51.
156.
2 68.
171.
2 52.
7 60.
7 60.
0 61.
3 65.
77.
80.
5 61.
2 69.
67.
0 70.
2 73.
83.
5 86.
2 69.
2 68.
3 66.
4 69.
0 71.
2 81.
6 85.
2 68.
1 58.
1 56.
6 60.
8 61.
8 73.
777.
2 59.
9 59.
2 57.
6 60.
147.
2 46.
5 39.
2 50.
5 62.
65.
3 46.
7 49.
3 46.
2 50.
7 38.
137.
2 38.
3 39.
2 51.
152.
3 37.
3 42.
6 37.
4 41.
4 30.
6 27.
7 30.
9 31.
2 42.
8 43.
0 26.
2 32.
2 27.
2 33.
0 29
6 18
2 22
2 26
18
5 20
6 19
7 33
3 20
6 33
. 15.
519.
8 31.
8 70.
7 48
Austin.—..
Belmont...
Eureka..
Fallon...
Las Vegas......
Logandale..
McGill.
Minden--
Quinn River Ranch-
Reno...
Tecoma_
Thorne.
Tonopah..
Winnemucca--
Erie__.
Franklin.,.....
Gettysburg..
Harrisburg....
Huntingdon....
Lewisburg ...
. 27.
. 26.
. 29.
29.
. 28.
- 25.
2 25.
5 24.
0 30.
9 29.
6 28.
4 25.
8 33.
6 35.
3 39.
0 39.
4 38.
8 35.
6 44.
7 46.
2 50.
151.
3 49.
3 48.
7 56.
3 58.
4 61.
5 62.
6 60.
2 58.
66.
0 65.
3 69.
170.
7 68.
5 67.
1 71.
6 70.
6 74.
0 74.
2 72.
2 71.
2 69.
5 68.
0 71.
7 72.
2 70.
5 68.
5 63.
3 62.
7 65.
7 66.
7 64.
9 62.
8 52.
3 51.
0 52.
0 54.
3 52.
0 50.
8 41.
3 39.
2 41.
4 43.
5 41.
2 39.
3 31.
6 29.
3 31.
0 33.
5 31.
1 29.
5 46
2 25
7 42
0 33
5 31
0 45
8 49
8 49
Madison—.
Medford..
Milwaukee--
Minocqua_
Prairie du Chien.
Waupaca__
. 16.
. 12.
- 20.
. 9.
. 17.
. 15.
6 18.
1 13.
4 22.
5 10.
219.
215.
6 31.
5 26.
1 32.
9 24.
4 33.
6 29.
0 45.
9 42.
0 43.
4 38.
2 48.
6 44.
6 57.
5 53.
4 53.
8 52.
2 59.
4 56.
4 67.
9 64.
7 63.
0 63.
8 69.
2 65.
1 72.
6 68.
7 70.
0 67.
0 73.
7 71.
1 69.
6 66.
0 69.
4 64.
7 70.
0 07.
7 62.
3 58.
0 62.
157.
8 63.
9 60.
1 50.
8 46.
2 50.
3 45.
4 51.
4 48.
2 35.
1 30.
5 36.
130.
9 36.
6 33.
3 22.
4 17.
8 25.
516.
4 23.
7 20.
4 42
9 30
6 50
2 17
2 33
1 24
26.
31.
23.
33.
30.
28.
3 30.
135.
127.
3 37.
133.
2 33.
9 40.
6 40.
4 36.
0 44.
6 40.
3 40.
3 46. 8 53.
7 47 9 S3.
3 61.
2 62.
3 69.
D 69.
6 67.
5 68.
Philadelphia..
Pittsburgh....
. 32.
. 31.
7 33.
0 31.
1 40.
3 39.
6 51.
6 50.
6 62.
9 62.
8 71.
5 70.
4 76.
6 74.
3 74.
7 72.
5 74.
7 72.
9 72.
1 69.
4 68.
7 66.
4 65.
2 63.
157.
4 54.
2 45.
9 42.
4 35.
7 33.
WYOMING
7 45.
2 50.
0 47.
0 46.
7 52.
2 59.
3 53.
s;53.
1
8 61.
0 66.
7 64.
9 62.
7 69.
3 74.
3 72.
7 70.
8 66.
3 74.
8 71/
9 69.
5 57.
2 64.
7 62.
2 45.
5 53.
5 50.
5 33.
5 43.
8 40.
8 24.
6 35.
9 30.
8 19
4 23
7 14
Reading__
Scranton—..
- 29.
_ 27.
9 30.
2 25.
0 39.
5 36.
4 51.
2 47.
1 61.
9 59.
9 70.
5 66.
6 53.
0 52.
9 42.
2 40.
6 30.
1
0 25
Bedford.-.
Cheyenne—.
Dubois.--.-
Ervay_—.-.
_ 17.
25.
4 19.
8 26.
3 27.
6 32.
6 37.
9 41.
2 46.
0 50.
0 53.
6 60.
2 59.
8 66.
8 58.
8 05.
6 50.
6 57.
8 40.
0 45.
3 29.9 17.
5 35. 0|28.
6 2C
1 43
3 59.
2 48.
2 37.
8 30.
2 42
SOUTH CAROLINA
, 20 .
. 21 .
- 20 .
. 26
- 18
6 22.
2 22.
0 21.
0 25.
6 22.
4 28.
2 29.
0 28.
5 35.
2 33.
6 37.
6 38.
4 38.
145.
0 42.
0 44.
2 47.
0 52.
0 58.
8 58.
2 65.
8 56.
0 63.
8 48.
4 54.
7 40.
0 42.
0 30. 8 21.
4 32. 3 21.
6 13
6 12
Evanston.
5 54.
2 50.
6 64.
8 60.
9 71.
4 68.
6 70.
2 66.
6 60.
2 56.
8 47 !
2 43.
4 36.
132.
0 26!
0 18.
4 26
8 16
NEW HAMPSHIRE
Allendale ..
Camden..
Charleston_
Cheraw—...
Florence__
. 48.
- 46.
. 49.
. 43.
. 45.
0 48.
147.
3 51.
7 45.
3 46.
3 57.
0 64.
3 73.
2 79.
0 83.
3 80.
3 75.
8 65.
355 .
5 47.
0 3 ;
Fort Laramie_
Green River-
Concord..
Hanover.
21.
17.
5 20.
17.
7 32.4;42.
5 28. 0|42.
7 55.
3 54.
163.
3 62.
2 69.8,66.
6 68.9 66.
5 59. 4i49.
0 58. 8 48.
4 36.
3 34.
8 25.
4 21.
2 IS
1 2C
8 54.
7 57.
0 53.
1 55.
3 62.
2 63.
4 61.
4 62.
5 69.
8 72.
5 70.
6 72.
577 .
4 78.
7 77.
2 78.
7 80.
5 81.
2 79.
4 81.
0 78.
3 80.
9 78.
2 80.
9 73.
3 76.
6 73.
2 74.
8 62.
2 67.
162.
6 64.
6 52.
158.
1 52.
1 53.
0 48.
1 51.
2 43.
9 44.
1 4
3 3
8 3'
9 3'
9 2!
0 3
Hyattville.
Lander--.
Laramie.-..
Lusk..
Pathfinder_
Pine Ridge..
.. 22
.. 19
.. 22
- 23
9 25
6 21
2 22
2 23
4 35.
7 31
6 29
2 31
2 45.
9 42.
8 37.
8 42.
a 43
2 50.
6 46.
2 51.
0 52.
8 50.
4 50.
7 60.
6 56.
6 61.
2 62.
3 62.
0 60.
2 66.
6 62.
5 67.
8 70.
2 69.
4 67.
9 65.
9 61.
8 66.
2 68.
8 68.
6 65.
4 55.
3 53.
4 56.
6 58
7 43.
5 42.
6 44.
7 46.
8 46.
2 43.
8 3o.
7 31.
0 32.
2 33.
2 35.
6 34.
8 33.
9 2u.
219.
2 21.
2124.
8 24.
5 21.
0 22.
4 26
8 26
3 2'
3 2
NEW' JERSEY
Georgetown..
Greenwood..
. 48.
_ 42.
8 49.
9 43.
1 57.
5 52.
5 63.
7 61.
5 72.
6 70.
2 71.
2 71.
169.
8 70.
1
2 78.
9 77.
8 78.
8 77.
4 76.
176.
4 80.
4 79.
0 80.
8 80.
0 79.
1 79.
5 80.
6 78.
6 79.
2 79.
1 77.
178.
4 75.
4 73.
5 74.
5 74.
5 72.
4 72.
6 66.
162.
3 64.
2 62.
0 61.
6 62.
1
3 56.
2 52.
5 54.
7 54.
150.
4 51.
1 48.
0 43.
- 17
.. 22
4 19
223
8 30
2 30
143.
8 41.
8 57.
2 55.
8 1.
1 I<
Atlantic City.
Trenton__
Vineland....
33.
32.
32.
3 32. 7 39.
131. 4 41.
2 32. 5 40.
3 47.
3 51.
5 51.
7 57.
5 62.
0 62.
3 66.
1 70.
3 71.
3 72.
3 75.
2 76.
4 72.3 67.
8 73. 7] 67.
2 73. 7 67.
0 56.
4 57.
0 56.
8 45.
2 45.
0 44.
436.
435.
1134.
2 47
0 27
5 51
Kingstree_
Saint Matthews_
Spartanburg...
Winthrop College.
- 47.
. 46.
_ 41.
_ 43.
7 47.
4 46.
6 42.
543.
5 56.
7 56.
8 51.
4 53.
6 63.
1 63.
160.
3 60.
7 46.
7 41.
7 43.
3 3'
9 4'
0 2
Sheridan—..
Shoshone Dam—.
Yellowstone Park-
.. 18
26
.. 18
9 22
429
0 19
4 32
0 35
7 27
7 43
3 44
0 37
4 50.
050
3 45
7 61.
8 61
5 53
1 67.
1 68.
9 61.
3 65.
6 67.
3 60
4 56.
5 58.
2 51.
3 43.
8 48.
4 40.
7 32.
2 38.
4 29.
8 22.
8 28.
2 20.
1 2.
6 1
7 3'
31
SUNSHINE AND WIND
Source of data. —The sunshine data collected by the
Weather Bureau are not entirely satisfactory, because
the automatic instruments in use up to the present
time do not indicate with sufficient accuracy the dif¬
ferent degrees of sunshine intensity. The electrical
thermometric recorder is used by the Weather Bureau.
This instrument consists essentially of a straight glass
tube with a cylindrical bulb at each end, the lower bulb,
as exposed for service, being coated on the outside with
lampblack. The whole is inclosed in a protecting glass
sheath, the space between the inner tube and the pro¬
tecting sheath being exhausted of air and hermetically
sealed. Mercury is used to separate the air in the bulbs,
and two platinum wires are inserted into the inner tube
about midway between the bulbs, but above the point
the top of the mercury column assumes in the absence of
sunshine. The ends of the wires within the inner tube
are slightly separated, but are so arranged
that the electric circuit will be closed by the
mercury coming in contact with them. The
instrument operates by the expansion of the
air in the lower blackened bulb and of the
mercury in the tube, when exposed to the
heat of sunshine, causing the top of the mer¬
cury column to move upward in the tube until
it comes in contact with the end of the wires
and thus closes the circuit. By this method
the record is automatically maintained until
in the absence of sunshine the mercury in the
tube recedes below the inserted wires, when
the circuit is broken.
The instrument is not delicate enough to
record sunshine in the early morning imme¬
diately after the sun appears above the hori¬
zon, and likewise the sun’s rays usually
become too weak to maintain a record a short
time before sunset. In such cases the actual
unrecorded sunshine is noted by personal
observation, and the records are corrected by
adding thereto, when the sun is shining, the
interval between the time of actual sunrise
and the beginning of the automatic record,
and between the ending of the record and the
time of actual sunset.
These instruments are located at the first-
order stations of the Weather Bureau only,
and their records constitute the sole source of data used
in the preparation of the several charts.
Length of day and 'possible sunshine. —Sunshine data
are usually expressed as the actual number of hours
of daily sunshine or in percentage of the possible amount.
Figures 88 and 89 show for the United States the pos¬
sible amount of sunshine or length of the day from sun¬
rise to sunset, for each tw T o and one-half degrees of
latitude, on December 22 and June 21, the winter and
summer solstices, respectively, and the shortest and
longest days of the year. At the time of the equinoxes,
about March 21 and September 22, the length of the
day, or total possible sunshine, is substantially
12 hours in all portions of the world.
The variation in the length of the day
from winter to summer increases with lati¬
tude. In the extreme southern portion of
the United States the days during the latter
part of June, or the longest of the year, are
only about three and one-half hours longer
than during the latter part of December, the
shortest days; but in the extreme northern
portion of the country the difference is nearly
eight hours. On clear days in early summer
the extreme Northern States receive about
two hours more sunshine than that received
in the Florida Peninsula and extreme southern
Texas, but in early winter the reverse is true.
Geographic variations in annual sunshine
percentage. —For the year as a whole the least
relative amount of sunshine in the United
States is received along the north Pacific
coast, where the averages are only about 40
per cent of the total hours from sunrise to
sunset, and in portions of the Great Lakes'
region and the central and northern Appa¬
lachian Mountain districts, wffiere somewhat
less than 50 per cent of the possible amount
is received. In the remaining districts east
of the Mississippi River and in the northern
border States from the Great Lakes westward to the
Rockies the average annual sunshine ranges between 50
and 60 per cent of the possible amount, except in por¬
tions of the Southeastern States, where it is somewhat
higher, especially in the Florida Peninsula. Between the
Mississippi River and the Rocky Mountains the annual
percentage is mostly between 60 and 70, which is true
also of the central portion of the Rocky Mountain and
interior Plateau regions. The maximum amount of
sunshine in the United States occurs in the far South¬
west, including extreme western Texas, and portions of
New Mexico, Arizona, and California. In southwestern
Arizona and the adjoining portion of California the sun
shines on the average for the year in nearly 90 per cent
of the total number of hours from sunrise to sunset.
Seasonal variations in amount of sunshine. —Figures 90
to 101, inclusive, show for the different sections of the
United States, and for each month of the year, the
average number of hours of daily sunshine, from which
the seasonal distribution of this important climatic
factor may be seen. Figures 102 to 105, inclusive, show
for the four seasons, winter, spring, summer, and fall,
the average percentage received of the total possible
amount of sunshine.
Because of the fewer hours of daylight and the greater
amount of cloudy weather in winter the amount of sun¬
shine is usually much less than in summer. Not only
are there fewer actual hours of sunshine in winter, but
the percentage of the possible amount is much less than
in summer. This is due to the fact that in winter
cyclonic action is more pronounced, and several succes¬
sive days of cloudy weather may be experienced in the
passing of a cyclonic storm, whereas in summer cloudy
weather and rainfall are usually of a more local character
and fewer entirely overcast days are experienced.
During the winter months more than half of the United
States, including nearly all districts from the Mississippi
Valley eastward and the central and northern districts
west of the Rocky Mountains, receive less than half
the amount of sunshine that would be received with
continuously clear sky. The Great Lakes region, west¬
ern Montana, northern Idaho, and western Washington
receive the least sunshine in winter, the average amount
in some of these localities being less than two hours
daily, or about one-fourth of that possible. In extreme
western Texas, most of New Mexico and Arizona, and
in southeastern California the winters are sunny, these
districts receiving on the average nearly eight hours of
sunshine daily.
With the advent of spring the amount of sunshine
increases rapidly, especially in the more northern dis¬
tricts. In portions of the upper Lakes region and of the
far Northwest, where in December and January the
average daily sunshine is only about two hours, in April
it is more than seven hours. The regions of least sun¬
shine during the spring months are along the north
Pacific coast, where only about 40 per cent of the possi¬
ble amount is received, and in the upper Ohio Valley
and the northern Appalachian Mountain districts, where
somewhat less than half the possible amount occurs.
The maximum amount of sunshine during this season
is received in the lower Colorado River Valley, where the
average for the- three spring months is 12 hours a day,
or about 90 per cent of the possible amount. Over most
of the Great Plains region the average sunshine in spring
ranges between 60 and 70 per cent of the possible amount
but in most districts to the eastward it is from 5 to 10
per cent less than this.
The increase in the amount of sunshine from winter
to summer in the northern portion of the United States
is very pronounced. In most of the northern
border States there are, on the average, in
July, about six and one-half hours more of
sunshine daily than in January. In the
South the increases are not so large, the daily
July excess over January in the central and
east Gulf States being only about two and
one-half hours. East of the Rocky Moun¬
tains the distribution of sunshine in summer
is the reverse of winter, as the northern dis¬
tricts receive more than the southern. In
much of the central and northern Great Plains
there is usually received in July from 40 to
50 per cent more sunshine than occurs along
the central and eastern Gulf coast. The
minimum amount of sunshine in summer
occurs along the central and northern Pacific
coast, where at some places only about 40
per cent of the possible amount is received,
and along the Gulf, the central and northern
Atlantic coasts, and in the Appalachian Moun¬
tain districts, where the average amounts are
somewhat less than 60 per cent of the pos¬
sible. The maximum amount of sunshine in
summer occurs in the Great Valley of Cali¬
fornia and over the western portion of the
interior Plateau region. The interior of Cali¬
fornia experiences practically cloudless skies
during the summer months, the average daily
amount of sunshine in most of the Great Valley being
nearly 14 hours, or about 95 per cent of the possible.
In fall, especially during October and November, much
cloudy weather is experienced in the region of the Great
Lakes, the upper Ohio Valley, and in the far Northwest.
In . western Washington the average daily amount of
sunshine in November is less than two hours. The
largest amount in fall occurs in the lower Colorado River
Valley, where the daily average is over nine hours. In
most of the important agricultural districts of the
country the fall sunshine averages between 55 and 65
per cent of the possible amount.
WIND
Importance of wind as a climatic factor .—
The most important function of w T ind is the
transportation of moisture from the oceans
and other large bodies of water to the land,
where it is condensed and precipitated in some
form of water, for the sustenance of plant and
animal life. The surface drift of the wind
has also a marked influence on the tempera¬
ture of many places, especially in localities to
the leeward of large bodies of water. The
on-shore drift of the wind gives to the Pacific
coast region of the United States compara¬
tively warm and equable winters and cool
summers. This influence is also felt, but to
a much less extent, on the leeward side of
the Great Lakes and likewise is in evidence
to some extent along the shores of smaller
bodies of water.
In addition to these climatic functions, air
movements have an important physiological
aspect. They produce a cooling tendency in
all conditions of temperature, by accelerating
the conduction of heat from the body and by
increasing the opportunity for evaporation,
which is a cooling process. The physical
effects of high temperatures, are very much
modified when accompained by brisk air movement.
But a low temperature which may be even stimulating in
a calm becomes unpleasant in windy weather.
Source of data. —There are two important aspects of
air movement which should be considered in studying the
relation of wind to climate, namely, velocity and direc¬
tion. The average hourly velocities of the wind for the
year as a whole in the different portions of the United States
are shown in Figure 106, and the average velocities at 3
p.m. local standard time, the approximate hour of greatest
wind movement, in Figure 107. These charts are based
on anemometer records for the 20-year period 1891 to
Figure 88 shows tor each two and one-half degrees of latitude the average time of sunrise and
sunset, mean solar time, and also the average length of the day, sunrise to sunset, on December 22,
the winter solstice, and the shortest day of the year. The length of the day from sunrise to sunset,
corresponding to the possible amount of daily sunshine, varies on December 22 from 10 hours and 35
minutes at latitude 25° N., the latitude of the southern end of Florida, to 8 hours and 10 minutes at
latitude 49° N., the northern boundary of the United States from Minnesota westward. It decreases
with increasing latitude until north of the Arctic Circle the sun does not rise above the horizon
Figure 89 shows for each two and one-half degrees of latitude the average time of sunrise and
sunset, mean solar time, and also the average length of the day, sunrise to sunset, on June 21, the
time of the summer solstice, and the longest day of the year. The length of the day from sunrise to
sunset, corresponding to the possible amount of daily sunshine, varies on June 21 from 13 hours and
41 minutes at latitude 25° N. to 16 hours and 19 minutes at latitude 49° N., increasing with the lati¬
tude until north of the Arctic Circle the sun on this day does not set and the day is 24 hours long
32
ATLAS OF AMERICAN AGRICULTURE
Figures 90 to 93 show for each month, from January to April, inclusive, the average daily amount of sunshine. In winter cloudy weather prevails in the Pacific Northwest and likewise in the region of the Great
Lakes. Over most of the State of Washington the average amount of sunshine received in January is only about 2 hours daily and in much of the Lake region it is only slightly more, but in the far Southwest the average
daily amount in this month is nearly 8 hours. With the advent of spring the amount of sunshine increases rapidly in the northern portion of the country and less rapidly in the southern. In the Pacific Northwest and
in the Great Lakes region the average amount of sunshine daily in April increases to about 7 hours. In the lower Colorado River Valley the sun shines in April, on the average, more than 12 hours daily, which is in excess
of 90 per cent of the possible amount. In the central and eastern United States the amount of sunshine in April averages 6^ to 8V£ hours per day, except in the northern Appalachian region, where less than 6}4 hours
are received
v
Figures 94 to 97 show for each month from May to August, inclusive, the average amount of daily sunshine. The excess of sunshine in summer over that of winter is much more pronounced in the North than in the
South. East of the Rockies the geographic distribution of sunshine in summer is the reverse of winter, the Northern States receiving more than the Southern. In much of the central and northern Great Plains the
average amount of sunshine in July is 40 to 50 per cent greater than along the central and east Gulf coast. The fewest hours of sunshine in the summer months are recorded along the north Pacific coast, and in the
central Appalachian Mountain region, where about one-half, or slightly more, of the possible amount is received. The maximum number of hours occurs in the Great Valley of California, where there is usually almost
continuous sunshine during the summer season, the average daily amount during July and August being nearly 14 hours, or about 95 per cent of the possible amount. In this region the drying of fruit in the sunshine is
an important industry
33
SUNSHINE
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Figure 99
AVERAGE NUMBER OF HOURS OF SUNSHINE DAILY
I ^ ^.OCTOBER \ I
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OKYLAHOM.
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(ARKAN,
SCALE OF SHADES
3 TO 4 HOURS
4 TO 5 HOURS
5 TO 6 HOURS
6 TO 7 HOURS
7 TO 8 HOURS
8 TO 9 HOURS
9 TO 10 HOURS
10 TO 11 HOURS
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Figures 98 to 101 show for each month from September to December, inclusive, the average amount of daily sunshine. With the advance of fall there is a pronounced diminution in the amount of sunshine in all
sections of the United States. This is due to the decreasing length of the days and to the increasing activity of cyclonic storms which often bring cloudy weather to large areas. During November and December cloudy
weather is experienced in most of the Lake region and in the far Northwest, where at some points the average amount of sunshine received daily is less than 2 hours. The maximum amount during fall and early winter
occurs in the far Southwest, where the average dally sunshine decreases from about 11 hours in September to somewhat less than 8 hours in December. The Mississippi Valley receives, in general, during September
7 to 9 hours of sunshine per day, during October from 6 to 8 hours, during November from 4 to 6.5 hours, and during December from 3 to 5.5 hours, the smaller amounts being in the Northeast and the larger amounts in
the Southwest
J
0
t
AVERAGE PER CENT ACTUAL SUNSHINE IN SPRING
-— j — CONSTITUTES OF TOTAL POSSIBLE _
- • 1 ^SUNSHINE ;
Figure 105
AVERAGE PER CENT ACTUAL SUNSHINE IN FALL
■—j -CONSTITUTES OF TOTAL POSSIBLE _
TE"" 1 50 ifcSUNSHINE \ 0 \T\~-W
'IGURE 103
rroisjr
ADo T
ADo
•KENT
OMS>
omM
jARKAN*
SCALE OF SHADES
_ 30 TO 40%
_ 40TO 50%
_ 50TO 60%
' 60 TO 70%
_ 70TO 80%
_ 80TO 90%
■ ' -[ 90 TO 100%
SCALE OF SHADES
zan 3oT °
_ 40TO 50%
_ 50TO 60%
_ 60TO 70%
W? 70TO 80%
_ 80 TO 90%
90 TO 100%
Figures 102 to 105 show for each season, winter, spring, summer, and fall, the average percentage which the sunshine actually received is of the total possible amount. These charts indicate for the different sections
of the country the average proportion of the day, regardless of its length, during which the sun shines, and also show the seasonal distribution of sunshine. The minimum amount of sunshine, both actual and percentage
of the possible, occurs in winter, when about half the United States, including all districts east of the Mississippi River, except the Gulf and south Atlantic coasts, receives on the average less than half the amount of
sunshine that would occur with continuously clear sky. The maximum amount of sunshine, both absolute and relative, occurs in summer, when practically the entire country, except the north Pacific coast and the
Appalachian Mountain region, receives more than 60 per cent of the possible'amount of sunshine, In the lower Colorado River Valley and in -the Great Valley of California the sun shines during the three summer months
during more than 90 per cent of the hours from sunrise to sunset
34
ATLAS OF AMERICAN AGRICULTURE
| Figure 105
AVERAGE VLLOCIIY OK THE WIND DURING THE YEAR
MILES PER HOUR
new/
SCALE OF SHADES
5 TO 6 MILES
6 TO 8 MILES'
8 TO 10 MILES
10 TO 12 MILES
12 TO 14 MILES
14 TO 16 MILES
Figure 106 shows the average velocity of the wind during the year in miles per hour, estimated for a uniform elevation of 100 feet above the surface of the earth. As a rule the highest average wind velocities occur in
the Great Plains region from northern Texas northward and along the coasts of large bodies of water, where the average velocity reaches 12 to 14 miles an hour. The smallest wind movement occurs, as a rule, in the
protected valleys of the West and Southwest, where at some places the average annual velocity is less than 6 miles per hour
Figure 107 shows the average velocity at 3 p. m., which is usually the time of the greatest wind movement during the 24-hour period. The average velocity at this hour is from 2 to 4 miles greater than that for the
entire day , .
Figures 108 and 109 show the prevailing direction of the wind during the months of January and July, respectively, the direction being indicated for each station by an arrow flying with the wind. In winter, winds
from a westerly or northerly direction are of frequent occurrence; but in summer, especially east of the Rocky Mountains, southerly winds are, in general, of most frequent occurrence and of longest duration
1910, inclusive, taken at about 175 first-order Weather
Bureau stations scattered throughout the United States.
For the first few hundred feet above the surface of
the earth wind velocity increases rapidly with increase
in elevation, and consequently for observed velocities to
be comparable over a large area, such as the United
States, the recording instruments should be exposed at
a uniform elevation above ground, and as far as pos¬
sible free from natural or artificial influences that would
tend to vitiate the records or render them of purely
local significance. Owing to the commercial demands
for prompt meteorological information it is often nec¬
essary to locate Weather Bureau offices in the centers
of large cities, where good exposure for the wind in¬
struments can not be had except by placing them at
considerable distances above the ground, and even then
the erection of new and taller buildings in the immediate
vicinity often interferes with the proper exposure ol
instruments and renders frequent changes in elevation
necessary. In view of these facts an effort has been
made to correct the recorded velocities at each station
to the velocity it is estimated the wind would have
attained at a unifrom elevation of 100 feet above the
ground, and applying, in each case where the station is
located in a large city, an approximated correction for
the city effect on wind movement. These approximated
values form the basis for Figures 106 and 107. In the
mountainous districts of the west the data refer only
to the lower valleys, where practically all the first-order
Weather Bureau stations are located. No attempt has
been made to show conditions at the higher elevations.
Geographic variation in wind velocity.— Over other
than water surfaces the highest wind velocities, as a
rule, occur in regions with large expanses of compara¬
tively level land, such as the Great Plains, and along
the coasts of large bodies of water. At points along
both ocean coasts and in the immediate vicinity of the
Great Lakes the average annual wind velocity is 12 to
14 miles, or more, per hour, which is also the case in the
Great Plains region, whereas over other districts east
of the Rocky Mountains it ranges generally from 8 to
10 miles per hour.
Daily march oj wind velocity.- —The daily march of
wind velocity as a rule, except at high elevations, fol¬
lows closely that of temperature, the minimum occurring
soon after sunrise and the maximum in the afternoon,
near the hour of maximum temperature. The average
velocity at 3 p. m. local standard time, shown in Figure
107, is from 2 to 4 miles per hour greater than the aver¬
age for the day, as shown in Figure 106. Figure 110
shows for Dodge City, Kans., representing the interior
of the country, the average diurnal march of wind
velocity for each month in the year. The action of
the sun’s heat in accelerating wind movement is clearly
shown by this graph, there being a regular increase in
velocity with the increase in power of the sun’s rays and
a corresponding diminution in the wind movement with
Figure 110 shows for Dodge City, Kans., representing the Great
Plains region, the diurnal march of surface wind velocity. This
follows closely the changes in temperature from hour to hour, the mini¬
mum velocity of the day occurri ng soon after sunrise and the maximum
from two to six hours after noon, varying with the season. In high
altitudes the daily march of wind velocity is the reverse of that at the
lower levels, the midday winds on Pikes Peak and Mount Washing¬
ton, for example, averaging only 75 to 85 per cent of the velocity at
midnight
decreasing temperature. Near the earth’s surface the
average increase in wind movement during the daylight
hours over that at night ranges generally from 20 to
40 per cent and is more pronounced in arid regions.
The daily march of wind velocity in elevated mountain
I districts is the reverse of that at low altitudes.
Prevailing wind direction. —The normal direction of
the surface winds in the United States in January
and in July is shown in Figures 108 and 109, respectively.
In winter, winds from a westerly or northerly direction
are most frequent, but in summer the prevailing direc¬
tion in most districts is southerly, especially from the
Rocky Mountains eastward. The prevailing direction
for the year as a whole is from some westerly point in
most sections of the United States.
Although practically the whole of the United States
lies within the region of the “westerlies,” common to
all middle latitudes, the weather is largely controlled
by the movements of areas of low and high barometric
pressure and the attendant characteristic winds peculiar
to each. These cause, particularly in winter, the fre¬
quent alternation of warm, moist southerly winds, with
cold, dry northerly winds, which when severe are com¬
monly called “cold waves.”
In addition to these interruptions to the prevailing
wind direction there are other special winds of uncer¬
tain and irregular occurrence, but with such marked
features and of such general climatic importance as
to require brief mention. The most important of these
are the “blizzard,” the “ hot winds,” and the “foehn”
or “chinook.” The blizzard is an occasional winter
visitor in the northern interior portion of the country,
and in exceptional cases extends far to the southward
and eastward. It is an intensely cold wind, usually
blowing from a northerly direction and accompained
by snow and ice crystals, continuing sometimes for
several days. Of directly opposite character are the
hot winds, which sometimes visit the interior of the
country during hot, dry weather, blowing generally
from the southwest with considerable force. In extreme
cases they have been described as similar to a blast
from a furnace, absorbing the small quantity of moisture
in the soil and literally drying up vegetation in the fields.
Immense damage may be done in a few hours by these
winds during critical periods of crop growth, but fortu¬
nately their occurrence is comparatively rare. The foehn,
locally known in the western United States as the
chinook, is usually a warm, dry wind, and is peculiar to
mountain regions. It occurs on the leeward side of
mountains and usually begins as a light breeze, but
frequently increases to high velocities. The warmth
and dryness of these winds rapidly melts and evaporates
the snow which makes it possible for animals, exposed
without shelter, to obtain food. Their influence at
times extends to a considerable distance onto the plains
bordering the Rocky Mountains on the east.
Joseph Burton Kincer.
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