PIPER FLORA OF THE STATE OF WASHINGTON. 



31 



As regards temperature then the climate of this region is remark- 

 ably equable, without marked extremes in either summer or winter. 

 The region in immediate proximity to the ocean has the coolest sum- 

 mer, and the extreme winter temperatures have never reached zero. 



EASTERN WASHINGTON. 



The records of the United States Weather Bureau concern nearly 

 forty different stations in eastern Washington for periods of from 

 one to twenty-three years. Fifteen of these stations lie within the 

 Upper Sonoran area, the remainder within the Arid Transition. The 

 Upper Sonoran stations are EUensburg, Ephrata, Kennewick, Lind, 

 Mottinger's Ranch, Moxee, Odessa, South EUensburg, Sunnyside, 

 Trinidad, Walla Walla, Wenache, and Zindel. The normal annual 

 mean temperature for the whole region is 48.7° ; for the Arid Transi- 

 tion stations alone it is 45.9° ; and for the Upper Sonoran stations it 

 is 51.3°. 



The normal monthly mean temperatures for the stations located in 

 the Arid Transition are as follows : 



Temperature data for Arid Transition area. 



Month. 



January. 

 February 



March 



April 



May 



June 



Degrees F. 



21 to 34 

 25 to 38 

 30 to 43 

 43 to 52 

 51 to 58 

 55 to 05 



Month. 



July.____- 



August 



September 



October 



November, 

 December. 



Degrees F. 



G2 to 72 

 02 to 74 

 51 to 03 

 44 to 55 

 32 to 42 

 25 to 36 



The highest temperature recorded at these stations is 105°, the 

 lowest is —32°. 



The corresponding data for the stations located in the Upper 

 Sonoran area are as follows : 



Temperature data for Upper Sonoran area. 



Month. 



January. 

 February 



March 



April 



May 



June 



Degrees F. 



25 to 37 

 25 to 39 

 39 to 49 

 48 to 55 

 55 to 63 

 59 to 71 



Month. 



July 



August 



September 



October 



November. 

 December- 



Degrees F. 



05 to 77 

 00 to 75 

 50 to 04 

 30 to 43 

 28 to 38 

 47 to 57 



The maximum temperature ever observed at any of the aboA^e 

 stations is 113° ; the minimum is — 30°. '' 



