New York Weather Bureau. 



493 



Frequency of Rainy Days. 



Thie accompanying taible showis the average frequency with 

 which a rain or snow fall amiouniting to oine omie-huiidredth of an 

 inch or moTe occurs, during each month, at six stations in New 

 Yoirk and also at Block Island, E. I., and at Brie, Pa.; the 

 formei' station representing, approximaitely, eastern Lo'Ug Island 

 and the latter souithwesitern New Yioirk. The rainy days are 

 here expressed in ipeTcentageis of the total nunnber of days in 

 each month, following the (method of the Signal Service charts, 

 from which the values at all stations excepting Ithaca were 

 deirived. The period of ohiservaition covers eighteen 3' ears at 

 Buffalo, Rochester, Oswego and New York city, isixteem years at 

 Erie, Pa., fifteen years at Albany, thirteen yea»s ait Ithaica and 

 eight years at Block Island. 



TABLE 27. 

 Percentage of Kainy Days. 



The proibability oif Tain foir all portions of the State may be 

 f-airly estimated from the averages at these staitions, although 

 some lo'cal variation muist be expected, especially in summer, 

 when local rains and thunderstormis are found to be quite 

 unequally disitributed over the Staite. It will be observed that 

 precipitaition occurs moist frequently during the winter months at 

 all staitioms, ibut, making due allowance foir this general tendency, 

 the inumber of rainy days is found tO' follow in a general way 

 the fluctuaitions oif the rain cnirves shioiwn in plates 3 and 4, which 

 fact may aid in 'the estimation of rain probability far vairious 



