50 RURAL NEW YORK 



intermediate levels are the most desirable farm sites. 

 Keference to the flow of water will often aid in 

 reaching an estimate of the air circulation and lia- 

 bility to frost of a particular section. 



Another element of temperature variation is the 

 direction of slope. South and east slopes are warm- 

 est and west and north slopes are colder in the order 

 named. 



The mean annual rainfall for New York State 

 ranges from 25 to more than 50 inches. The lowest 

 rainfall occurs on the Great Lakes plain, in the cen- 

 tral lakes region and in the upper part of the Cham- 

 plain Valley. 



The higher amount of rainfall is also in three 

 regions, on the southwest slope of the Adirondack 

 Mountains, on Long Island and over the heel of 

 the State in the lower Hudson Valley. The Cat- 

 skill Mountains and the eastern plateau section have 

 a relatively high rainfall. The prevailing winds as 

 they move east over the Great Lakes strike the rising 

 country of the Adirondacks and by passing up this 

 slope are lowered in temperature so that a part of 

 their moisture must be precipitated. The same thing 

 occurs to the winds that sweep up from the Atlantic 

 and encounter the highlands in the lower part of 

 the Hudson Valley and Catskills. On the other 

 hand, the low rainfall in the Central Lakes region and 

 the Champlain Valley occurs where the wind has 

 passed over an elevation and its capacity for moisture 

 is increased by its rising temperature. On the Great 

 Lakes shore the wind from the lakes encounters the 



