Philadelphia sits at the seam between the humid-subtropical South and the humid-continental Northeast, which makes its weather feel like neither and both. Summers are hot and thundery, with August the wettest month and dew points high enough to make a rowhouse stoop unbearable by mid-afternoon. Wednesdays tend to be the rainiest day of the week across the long record — an artifact of the midweek aerosol-CCN cycle. Winters bring a mix of rain, ice, and snow that's hard to predict more than a few days out, and the occasional nor'easter that drops a foot at once.
Climate and Average Weather Year Round in Philadelphia
Year-round temperature
In Philadelphia, the warmest months are June through September, with average daily highs between 80°F and 89°F. The coldest stretch runs December through February, with highs between 42°F and 47°F and overnight lows reaching 28°F.
Rainfall through the year
Rainfall in Philadelphia averages 4.2 in per month over the long run. August is the wettest at 5.0 in, while February is the driest at 3.3 in.
Days at 90 °F or hotter
Philadelphia averages 39.5 days per year at 90 °F or hotter. The hottest year on record saw 73 such days (2005); the coolest just 16 (2009).
Precipitation this year
As of May 28, Philadelphia has received 1.2 in of precipitation this year — 94% below the long-term normal for this point in the year (19.2 in).