4 
The Colorado Experiment Station 
a bracing, invigorating climate stimulates the people as a 
whole to their best efforts in any line of work or endeavor. 
MEAN TEMPERATURE AND PRECIPITATION 
The mean temperature of the State as a whole is 45 de¬ 
grees. The precipitation varies. In the eastern counties it 
averages 17 to 18 inches, it diminishes gradually to a point 
somewhere east of the foothills, where the average is about 
15 inches, and from this point it increases so that on some of 
the high mountain watersheds it will be considerably more. 
The high mountain parks are dependent upon the mountain 
barriers surrounding them for the rain they receive. In North 
Park the average is around 15 inches, while in the San Lnis 
Valley it is only about 7 to 8 inches. On the Western Slope the 
location in respect to mountain ranges and prevailing winds 
causes considerable variation. 
Our position, south of the track of the majority of the 
storms as they cross from north of Montana to the Great Lakes 
and beyond, and in the interior of the continent, remote from 
the ocean, with our differences in altitude and diversified topo¬ 
graphy, greatly modify the climate at different points. The 
usual track of storms being some distance northward, the 
State is generally dominated by the warm and dry quadrants 
of the low areas that move eastward with great regularity, and 
escapes in part the attendant precipitation of moisture, the 
high wind movement and the sharp fluctuations of tempera¬ 
ture. Considering the great distance from the Pacific and the 
high mountain ranges which the westerly winds must cross, 
it is not surprising that the low humidity is attended by a 
great range of temperature. 
Normal pressure distribution, with its effect on the result¬ 
ing direction of the winds, causes an important effect on our 
climate. During the winter the high pressure of the Salt Lake 
region remains fairly constant, and the effect this has on any 
locality depends upon its location, whether east or west of the 
mountains. To the west is found persistent cold for the lati¬ 
tude and altitude, especially in some of the higher valleys. 
The clear skies and still atmosphere cause radiation to proceed 
rapidly, and the topography causes a steady flow of cold air 
from the higher points into the valleys. On the eastern slope 
at such times the resulting winds are westerly, coming over 
the mountains, the air being warmed by compression during 
the descent to the foothills and plains, the mean temperature 
is raised considerably, and the capacity of the air for mois¬ 
ture is increased, so that there prevails in the eastern half of 
