56 Gen. A. W.Greely — Rainfall Types of the United States. 



the mid or late autumn, the increases until early spring being 

 very small and irregular. Generally, it may be said that a well 

 marked tendency obtains along the coast toward August as the 

 month of maximum rainfall. With increasing distance from 

 the Atlantic ocean, and probably owing to influence of the trans- 

 Appalachian types, the time of greatest precipitation generally 

 shifts to July, while the minimum rainfall, which occurs during 

 November from Florida to western New York, gradually changes 

 to October along the slope of the Appalachian range and the 

 upper Ohio valley, as shown in both phases by the records of 

 Augusta, Georgia, and Pittsburg, Pennsylvania. 



The effect of interference of the Saint Lawrence type extend- 

 ing southAvard is evident at Troy, New York, in its minimum of 

 February and March, and even as far as Philadelphia it exercises 

 a very slight influence. 



Normal daily Rainfall and Departures therefrom. 



( Values are in fractions of an inch.) 



STATIONS. 



<^ Co 

 MS2 



p- >,l 



DEPARTURES. 



January ... 

 February.. 



March 



April 



May 



June 



July 



August 



September 



October 



November. 

 December 



— .010 



— .002 



— .006 



— .008 

 .007 

 .006 

 .003 

 .025 



— .004 



— .011 

 .000 



— .003 



