 Precipitation is generally spread throughout the year, with eight to eleven wet days per month, at an average annual rate of , but historically ranging from in 1922 to in 2011.The most rain recorded in one day occurred on July 28, 2013 when fell at Philadelphia International Airport.Philadelphia has a moderately sunny climate with an average of 2,500 hours of sunshine annually, and a percentage of sunshine ranging from 47% in December to 61% in June, July, and August.