Philadelphia has chilly winters and warm summers. A typical July afternoon reaches 87°, a January night drops to 25°, and about 23 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normalsUpdated once a decade
☀️
July high
87°
60th hottest of 3,547 Pennsylvania towns
❄️
January low
25°
40th mildest of 3,547 Pennsylvania towns
💧
Rain + melted snow
47 in
969th wettest of 3,547 Pennsylvania towns
🌨️
Snow a winter
23 in
562nd least snowy of 3,541 Pennsylvania towns
A normal year
What a year in Philadelphia feels like
❄️
Winter
44° / 27°
Typical high / low · 5 days with an inch or more of snow
🌷
Spring
63° / 43°
Typical high / low · Last frost around Apr 15
☀️
Summer
85° / 65°
Typical high / low · 33 days reach 90° in a normal year
🍂
Fall
67° / 48°
Typical high / low · First frost around Oct 31
10°
20°
40°
50°
60°
70°
80°
90°
100°
32°
41°
25°
44°
26°
52°
33°
64°
43°
74°
53°
83°
62°
87°
68°
85°
66°
79°
59°
67°
47°
56°
37°
46°
30°
JanJFebFMarMAprAMayMJunJJulJAugASepSOctONovNDecD
32°, freezingBar runs from the typical overnight low up to the afternoon high
Best months to be outsideAprMayJunSepOctHighs of 62–84° and lows of 40° or more
Month by month
Philadelphia weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
Month
High
Low
Rain + melt
Snow
Wet days
Snow on ground
30-yr range
January
41°
25°
3.4"
7.1"
11
5
25° – 40°
February
44°
26°
2.8"
8.4"
10
6
24° – 43°
March
52°
33°
4.1"
3.6"
11
2
37° – 51°
April
64°
43°
3.7"
0.3"
11
0
50° – 58°
May
74°
53°
3.8"
0
11
0
58° – 69°
June
83°
62°
4.2"
0
10
0
69° – 76°
July
87°
68°
4.8"
0
10
0
73° – 81°
August
85°
66°
4.4"
0
9
0
71° – 80°
September
79°
59°
4.4"
0
9
0
65° – 73°
October
67°
47°
3.9"
0
9
0
52° – 63°
November
56°
37°
3.3"
0.2"
9
0
41° – 51°
December
46°
30°
4.2"
3.5"
11
3
30° – 50°
Year
65°
46°
46.9"
23.1"
121
16
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain & snow
Rain and snow in Philadelphia
Philadelphia gets 47 inches of rain and melted snow a year. July is the wettest month and February the driest. Rain or snow falls on about 121 days a year. Snow covers the ground about 16 days of the year.
💧
47 in
Rain + melted snow a year
More rain than 77% of U.S. towns
❄️
23 in
Snow in a normal winter
Less snow than 53% of U.S. towns
⛄
16 days
With 1"+ of snow on the ground
Fewer than 63% of U.S. towns
Rain + melted snow by month
Inches of water
4.8"
JFMAMJJASOND
Snowfall by month
Inches of snow
8.4"
JFMAMJJASOND
Frost & the growing season
About 199 frost-free days a year
In half of years the last 32° night comes by April 15 and the first one by October 31. That leaves about 199 frost-free days for gardens, longer than 72% of U.S. towns.
🌱 Apr 15
🍂 Oct 31
199 frost-free days
JFMAMJJASOND
🥶
103
nights at or below 32° in a normal year
🧊
<1
nights below 0° in a normal year
🔥
33
days that reach 90° in a normal year
Freezing nights by month
Average nights at or below 32°
JFMAMJJASOND
90° days by month
Average days at 90° or more
JFMAMJJASOND
Heating & cooling
Heating and cooling a home in Philadelphia
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Philadelphia, 81% of that work is heating and 19% is cooling, so the furnace matters far more than the air conditioner.
🔥
4,858 heating degree daysLess heating than 68% of U.S. towns
❄️
1,171 cooling degree daysMore cooling than 68% of U.S. towns
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
Around Philadelphia
Philadelphia and its neighbors
Philadelphia borders 12 towns with climate data. January nights across them vary by 2.3°. Lower Merion has the coldest January nights (24°) and Tinicum the hottest July afternoons (88°). Philadelphia’s January low is 25° and its July high 87°.
Compared with every U.S. town and city on TownTapestry, each counted once.
Then and now
Warmer than it used to be
+2.1°1991–2020 average vs. the 20th century (1901–2000)
The last 30 years in Philadelphia averaged 2.1° warmer than the 1900s. The biggest change is in December (+3.7°). The shift is larger than in 96% of U.S. towns.
❄️ Winter+3.0°now 35°, was 32°
🌷 Spring+1.8°now 53°, was 51°
☀️ Summer+2.0°now 75°, was 73°
🍂 Fall+1.8°now 57°, was 56°
Change by month1991–2020 average minus 1901–2000 average, at Philadelphia’s spot on NOAA’s grid
+1.3°
+3.7°
JanJFebFMarMAprAMayMJunJJulJAugASepSOctONovNDecD
Year to year
How much a month can swing
A normal is an average, and real years wander around it. December swings the most: between 1991 and 2020 its average temperature ranged from 30° to 50°. June is the most reliable, staying within 7°.
10°
20°
30°
40°
50°
60°
70°
80°
90°
JanJFebFMarMAprAMayMJunJJulJAugASepSOctONovNDecD
Coldest to warmest month in 30 yearsNormal
Questions
Common questions about Philadelphia’s climate
What is the coldest month in Philadelphia?
January, with a typical high of 41° and a low of 25°.
What is the hottest month in Philadelphia?
July, with a typical high of 87° and a low of 68°. About 33 days a year reach 90°.
How much snow does Philadelphia get?
About 23 inches in a normal winter, most of it in February.
When is the first frost in Philadelphia?
In half of years the first 32° night comes by October 31, and the last spring frost by April 15.
What is the rainiest month in Philadelphia?
July, with 4.8 inches of rain and melted snow. The year totals 47 inches.
📍Temperatures and rainfall come from NOAA’s gridded climate normals for Philadelphia itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Philadelphia Intl Airport, PA (11 mi, snow) and Pennsauken 1n, NJ (7 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.