Climatic Conditions in Oregon. 91 



UMATILLA COUNTY. 



Umatilla County is situated on the northwestern slope of the Blue 

 Mountains and fronts on the Columbia River. It contains much diversity 

 of climate. At Umatilla, on the Columbia River, the elevation is 340 

 feet; annual temperature, 52.5 degrees; April, 54.6; July, 75.4; October, 

 54.3; annual rainfall, 8.53 inches. At Pendieton, the county seat, the 

 elevation is. 1,817 feet; annual temperature, 51.9 degrees; January, 33.2; 

 April, 51.6; July, 71.6; October, 51.5; annual rainfall, 14.16 inches; 

 length of season between killing frosts, 150 days. At Weston the ele- 

 vation is 1,800 feet; annual temperature, 48.6 degrees; annual rainfall, 

 23.89 inches. 



UNION COUNTY. 



Union County is in large part a round Valley amid the Blue 

 and other mountains. La Grande, the county seat, is at an elevation of 

 2,874 feet. The annual temperature is 48.3 degrees; January, 33.1; 

 April, 47.7; July, 70.5; October, 49.4; annual rainfall, 19.12 inches. 

 Much fruit is grown in this county without irrigation. 



WALLOWA COUNTY. 



Wallowa County is in the northeastern corner of the State and a 

 large proportion of the county is mountainous. The elevation at Wallowa 

 is 2,935 feet; annual temperature, 43.2 degrees; annual rainfall, 13.09 

 inches. Joseph is at an elevation of 4,400 feet. Its annual temperature 

 is 42.3 degrees; January, 23.5; July, 62.6; annual rainfall, 20.40 inches. 



WASCO COUNTY. 



Wasco County fronts on the Columbia River and is just east of the 

 Cascade Mountains. The altitude at The Dalles, the county seat, is 112 

 feet; the annual temperature, 52.5 degrees; January, 32.2; April, 53.5; 

 July, 71.3; October, 52.4; annual rainfall, 14.97 inches; average length 

 of season between killing frosts, 209 days, or about the same as at 

 Greenville, South Carolina. At Wamic at a much higher altitude, near 

 the center of the county, the annual temperature is 47.6 degrees; annual 

 rainfall, 16.15 inches. 



WASHINGTON COUNTY. 



A large share of Washington County lies below 500 feet altitude, 

 but there is also much arable land at higher altitudes. At Forest Grove 

 the altitude is 220 feet; annual temperature, 51 degrees; January, 37.1; 

 April, 49.4; July, 65.4; October, 51.8; annual rainfall, 48.92 inches. 



WHEELER COUNTY. 



Wheeler County is in the north central portion of eastern Oregon. 

 Weather observations are not available but conditions do not greatly 

 vary from those of Grant County. 



YAMHILL COUNTY. 



Much of Yamhill County lies at an altitude of less than 500 feet but 

 a large share of the orchards of the county are found at higher altitudes. 

 McMinnville, the county seat, is at an altitude of 182 feet. The annual 

 temperature is 51.5 degrees; January, 38.6; April, 50.3; July, 64.7; 

 October, 52.7; annual rainfall, 46.74 inches. Records kept at Fort 

 Yamhill, in the western part of the county for the period 1857-1865, 

 showed an annual temperature of 49.3 degrees; January, 37.1; April, 

 47.8; July, 60.9; October, 51.2; annual rainfall, 55.57 inches. 



