Philadelphia, PA Climate & Monthly Averages

Pennsylvania, United States 🇺🇸 · humid subtropical climate
Annual avg
56°
Hottest month
July
Coldest month
January
Rainy days / yr
129
Sunshine
8.6 h/day
Right now: 84° and cloudy - see live conditions

The climate of Philadelphia

Seasons are the whole story in Philadelphia. The gap between an average July and an average January is 25°C - hot, humid summers and generally mild winters - which in practice means 88°F (31°C) afternoons at one end of the calendar and 42°F (5°C) at the other.

Climate quick facts

  • Hottest month: July - highs near 88°F (31°C)
  • Coldest month: January - highs near 42°F (5°C)
  • Decade extremes (2015-2024): 99°F (37°C) high · -7°F (-22°C) low
  • Wettest month: July (14 rainy days) · Sunniest: July (11.6 h sun/day)
  • Climate type: humid subtropical
  • Annual swing: 25°C between the average warmest and coolest month · day to night: 9°C
  • Snow: about 9 days a year
  • Months averaging 30°C or hotter: 1
  • Average humidity: 68%

Temperatures through the year

January is the coolest month, with highs of 42°F (5°C) and lows near 27°F (-3°C). At its warmest, in July, Philadelphia runs to 88°F (31°C) in the afternoon and back to 70°F (21°C) by dawn. Snow falls on roughly 9 days a year, mostly December through March.

Rain, sun and snow

Between the average July and the average January lie 25°C, a wider spread than roughly 81% of the cities we track. Overnight lows average at or below freezing for 2 months, January through February. The gridded 2015-2024 daily record for this location tops out at 99°F (37°C) and bottoms at -7°F (-22°C) - decade extremes, not all-time station records.

How Philadelphia compares

  • 28% of the year's precipitation falls in its wettest three months - more evenly spread than almost every other city we track.

Ranked against every city in our dataset, each measured on the same ten-year window.

Monthly climate table

Monthly averages for Philadelphia based on 2015–2024 weather data.
MonthHighLow Rain daysPrecipitation SunshineHumidity
January 42° 27° 10 3.6 in 6.0 h/day 66%
February 46° 28° 10 3.5 in 6.9 h/day 66%
March 53° 34° 10 4.3 in 7.9 h/day 63%
April 63° 44° 11 4.2 in 8.9 h/day 64%
May 73° 54° 12 4.2 in 9.7 h/day 68%
June 82° 64° 12 4.2 in 11.2 h/day 67%
July 88° 70° 14 4.7 in 11.6 h/day 70%
August 85° 69° 12 4.5 in 10.7 h/day 71%
September 79° 62° 10 4.1 in 9.0 h/day 71%
October 68° 51° 9 3.8 in 7.9 h/day 71%
November 56° 39° 8 3.0 in 7.4 h/day 68%
December 47° 33° 10 4.3 in 5.8 h/day 71%

Philadelphia month by month

Philadelphia weather in January

January brings highs around 42°F (5°C), lows near 27°F (-3°C), about 10 wet days and roughly 3 snowy days - typically the coldest month of the year in Philadelphia.

Philadelphia weather in February

February brings highs around 46°F (8°C), lows near 28°F (-2°C), about 10 wet days and roughly 3 snowy days.

Philadelphia weather in March

March brings highs around 53°F (12°C), lows near 34°F (1°C), about 10 wet days and roughly 2 snowy days.

Philadelphia weather in April

April brings highs around 63°F (17°C), lows near 44°F (7°C), about 11 wet days.

Philadelphia weather in May

May brings highs around 73°F (23°C), lows near 54°F (12°C), about 12 wet days.

Philadelphia weather in June

June brings highs around 82°F (28°C), lows near 64°F (18°C), about 12 wet days.

Philadelphia weather in July

July brings highs around 88°F (31°C), lows near 70°F (21°C), about 14 wet days - typically the hottest month and the wettest month and the sunniest month of the year in Philadelphia.

Philadelphia weather in August

August brings highs around 85°F (30°C), lows near 69°F (20°C), about 12 wet days.

Philadelphia weather in September

September brings highs around 79°F (26°C), lows near 62°F (17°C), about 10 wet days.

Philadelphia weather in October

October brings highs around 68°F (20°C), lows near 51°F (11°C), about 9 wet days.

Philadelphia weather in November

November brings highs around 56°F (13°C), lows near 39°F (4°C), about 8 wet days - typically the driest month of the year in Philadelphia.

Philadelphia weather in December

December brings highs around 47°F (8°C), lows near 33°F (0°C), about 10 wet days.

Seasons in Philadelphia

Spring (March through May)

Through spring, Philadelphia runs cool rather than cold: 63°F (17°C) by day, 44°F (7°C) after dark, and rain falls on around 34 of the 90 days, plus about 2 snowy days.

Summer (June through August)

Summer in Philadelphia sits firmly in the heat, with daytime highs averaging 85°F (29°C) and nights around 67°F (20°C); rain falls on around 38 of the 90 days. Daylight is generous - around 11.2 hours of sun a day. With the moisture factored in, afternoons feel hotter than the reading suggests - the humidity and dew point converter shows why.

Fall (September through November)

Fall in Philadelphia is mild, with daytime highs averaging 68°F (20°C) and nights around 51°F (11°C); expect showers on roughly 27 days across the season.

Winter (December through February)

Winter in Philadelphia is brisk and cold, with daytime highs averaging 45°F (7°C) and nights around 29°F (-1°C); rain falls on around 31 of the 90 days, plus about 6 snowy days.

Climate questions, answered

How often does it rain in Philadelphia?
About 129 days bring measurable precipitation, totalling 48.6 inches (1233 mm). That works out at roughly 9.6 mm on an average wet day.
Is Philadelphia cold in winter?
January nights average 27°F (-3°C). Frost and occasional ice are part of the season.
How hot does Philadelphia get in summer?
July averages 88°F (31°C). Hot afternoons happen but extremes are not the norm.
Is Philadelphia humid?
Relative humidity averages 68% across the year, which reads as fairly humid. Paired with July heat, muggy afternoons are routine.

Best time to visit Philadelphia

Aim for April to June and September to October if you get the choice: warm days, manageable rainfall and plenty of daylight line up, and highs average 73°F (23°C) against roughly 11 wet days a month. For the same question asked the other way round, see where else is warm in April.

Pack for Philadelphia with light clothing for the warm months, a warm jacket and layers for the cooler season and a compact umbrella or rain shell. Note the gap between afternoon and night: July pairs 88°F (31°C) with 70°F (21°C).

Philadelphia temperature records (2015-2024)

Highest recorded
99°
in June
Lowest recorded
-7°
in January
Annual precipitation
48.5"
Snowy days / yr
9

Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.