VALLEY OF THE MINNESOTA RIVER. 



577 



Through the kindness of Director Harmon of the Minnesota 

 Weather Service, I have been able to compile from records pre- 

 served on file in his office at Minneapolis the following tables 

 of precipitation and temperature of three important points in 

 the valley of the Minnesota. St. Paul is near the mouth of the 

 main stream. Mankato is in the southern central region. 

 Morris is in the northwestern region. Thus the points are 

 fairly illustrative. The figures represent averages of monthly 

 means and summations of averages for the average yearly 

 mean. The period covered by the observations is six years. 



TABLE OF PRECIPITATION. 



Morris: lat. 45" 30'; long. 95" 58'; alt. 1,129 feet. 

 St. Paul: lat. 44° 58'; long. 93° 03'; alt. 693 feet. 

 Mankato: lat. 44° 06'; long. 94° 01'; alt. 791 feet. 



TABLE OF TEMPERATURE. 



Prom these tables it is seen that the range of temperature 

 is somewhat higher in the eastern than in the western portion 

 of the valley and somewhat higher, too, in the southern than in 

 the northern. The precipitation is greater in the north- 

 eastern corner than elsewhere. This is, however, the prin- 

 cipal position of the forest area of the valley. It is probable 

 that forest and rainfall have a reciprocal influence upon each 

 other. 



So far as the data of prevailing winds have been examined 

 it is impossible to make any valuable generalisations from them 

 except that the shape of the valley produces some diversions in 

 different portions. What these diversions are or what law 

 governs them, I am unable to say. 



Average cloudiness is unfortunately not a matter of record 

 to such an extent that anything can be done with it. 

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