Temperature for May
In Philadelphia, PA during May the average high temperature is 76.0°F. The hottest day on record was May 30, 1991 when the temperature hit 96.1°F.
Precipitation for May
In May the average monthly rainfall in Philadelphia, PA is 4.61 inches with rain usually falling on between 12 and 13 days. 1986 was the driest May with only 0.70 inches of rain falling, and 1973 was the wettest May with 22.28 inches of rain. The wettest single day in May was 3 May 1973 when 11.02 inches of rain fell.
There are thunderstorms on between 3 and 4 days in May.