Table 33. -- Time of season by which ground is thawed to various depths 

 (Av. 1950-58) 



Date 





Ft. Yukon 



Northway 



Anchorage 



Bettles 



Big Delta 



Summit 



Fairbanks 



Tanana 



Kotzebue 



Unalaklee 



Gulkana 



Galena 



McGrath 

















6" 



Depth 















April 



1 





1/ 



























11 





X 

























on 







X 























May 



1 







X 





X 





X 



X 





X 



X 









11 







X 



X 



X 



X 



X 



X 





X 



X 



X 



X 





21 



X 





X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



June 



1 



X 





X 



X 



X 



X 



X 



X 



■ X 



X 



X 



X 



X 





11 



X 





X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 





21 



y 





A 



X 



X 



X 



12" 



X 



Depth 



X 



X 



X 



X 



X 



X 



April 



1 

 11 



on 







X 























May 



1 

 11 







X 



X 





X 

 X 



X 



X 

 X 



X 





X 











on 



21 



X 





X 



X 



X 



X 



X 



X 





X 



X 



X 



X 



June 



1 



X 



X 



X 



X 



X 



X 



X 



X 





X 



X 



X 



X 





11 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 





21 



X 



x 



x 



x 





-'- 



24" 



X 



Depth 



X 



X 



X 



X 



X 



X 



April 



1 

 11 





























May 



1 



X J. 







X 

 X 

























21 







X 



X 



X 



X 



X 



X 





;■: 





X 



X 



June 



1 







X 



X 



X 



X 



X 



X 





X 



X 



X 



X 





11 



X 





X 



X 



X 



X 



X 



X 





X 



X 



X 



X 





21 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



1/ No 



data 



for 6 



-inch 



depth . 





















Source: United States Weather Bureau compilation. 



141 



