Summer
Late July and August are hot. Temperatures in July average a low of 21ºC and high of 30ºC, but frequent heat waves can push temperatures up to 35ºC, with the humidity sometimes bringing the heat index up to 43ºC.
The warmest month of the year is July with an average maximum temperature of 85.50 degrees Fahrenheit. Temperature variations between night and day tend to be fairly limited during summer with a difference that can reach 16 degrees Fahrenheit. The annual average precipitation at Philadelphia is 42.05 Inches. Rainfall in is fairly evenly distributed throughout the year. The wettest month of the year is July with an average rainfall of 4.39 Inches.