THE CLIMATE OF MICHIGAN. 



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winter, as shown in Chart VIII. Along the shore of Lake Michigan from 

 fifty to sixty inches per year is the average, bnt in the interior of the 

 state the snowfall totals from thirty to fifty inches annually, in most 

 sections. In the southern portion of the upper peninsula the snowfall 

 is less than fifty inches. This heavy snowfall along the lakes is caused 

 by the passage of the prevailing westerly winds, first over the compara- 



120'; 



CHART VIII. -Average annual snowfall, in inches. 



tively warm water of Lakes Michigan and Superior, for distances of 

 sixty to over one hundred miles, causing them to become moisture 

 laden, and then on coming in contact with the cold land areas along 

 the shore the moisture is condensed and falls as snow almost con- 

 tinualh', at least while the winds continue on shore, during the winter 

 season. The ground is usually covered in the Lake Superior region, 

 with one to five feet of snow, from middle autumn to late spring. 



The fourth factor controlling climate, i. e., the proximity of the normal 

 storm i»ath, is a very important one as regards rainfall. Ordinarily 

 each successive low pressure area brings more or less rain or snow as it 



