81 



Monthly and Annual Mean Surface iVater Tanperatures, °F 



FORT -.VASHINGTON, MD., POTOMAC RIVER 38°42'45"N. 77°02'15"W. 



Oct. Nov. Dec. Ann. 



62.5 48.1 35.2 - 



65.8 50.1 33.4 57.3 



61.6 46.8 40.2 58.3 



56.7 50.3 37.2 56.2 

 56.4 47.9 40.8 56.6 

 59.2 48.9 36.3 58.6 



1891 35.8 43.1 41.9 56.9 65.3 73.7 78.6 79.4 76.1 61.8 48.1 40.7 58.4 

 92 35.6 38.0 -_---__ ____ 



(7) (7) (6) (6) (6) (6) (7) (7) (7) (7) (7) (7) 



Mean 35.7 38.0 41.5 55.0 66.7 75.8 79.5 78.9 72.8 60.6 48.6 37.7 57.6 



Readings at first high water and first low water after 7 a.m. 

 Source - OSCFF 



