PIPER FLORA OF THE STATE OF WASHINGTON. 



31 



As regards teniperatui'e then the climate of this region is remark- 

 ably equable, without niarkeil extremes in either sunnner or winter. 

 The region in immediate ])roximity 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 dift'erent 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 Avithin the Arid Transition. The 

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

 Mottinger's Eanch, Moxee, Odessa, South Ellensburg, Sunnyside, 

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

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

 tion stations alone it is -15.9° ; and for the Upper Sonoran stations it 

 is 51.3°. 



The nornuil monthly mean tenijjeratures for the stations located in 

 the Arid Transition are as follows: 



Ti'itiitrnituic (lata for Arid 'rransitioii area. 



Month. 



J a nil a ry. 

 Febi'iiarj' 

 Maivlu_. 



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. 



02 to 72 

 02 to 74 

 51 to 03 

 44 to 55 

 32 to 42 

 25 to 30 



The highest temi)erature recorded at these stations is 105°, the 

 loAvest is —32°. 



The corresponding data for the stations located in the Upper 

 Sonoran area are as follows : 



Temperature data for Upper Honoraii area. 



The maximum temperature ever observed at any of the above 

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



