Pottstown, Pennsylvania climate: Normal weather by month, frost dates and records
Pottstown's normal year runs from 22°F January nights to 84°F July afternoons, with 45.3 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 11.1°C, January lows of −6°C, July highs of 29°C, 1,152 mm of precipitation a year.
- NOAA stationPottstown Limerick Airport
- Station IDUSW00054782
- Location40.24°N 75.56°W
- Elevation291 ft (89 m)
- From the center5 miles
- Population23,553
On October 14, the normal high in Pottstown is 64°F and the normal low 44°F, and the chance of measurable rain or snow is 38%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Pottstown.
- Jan 37° 22°
- Feb 40° 23°
- Mar 49° 30°
- Apr 61° 40°
- May 71° 50°
- Jun 79° 59°
- Jul 84° 64°
- Aug 82° 62°
- Sep 75° 55°
- Oct 63° 43°
- Nov 52° 34°
- Dec 42° 27°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Pottstown each month?
July is the warmest month, with normal highs of 84°F; January the coldest, with normal lows of 22°F. The most precipitation falls in September (4.83 in), the least in February (2.56 in).
Each month has its own page with the day-by-day normals, the month's records and its recent years:
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 37°F | 22°F | 29.7°F | 3.02 | 10 | <1 | 26 | 9 h 40 min |
| February | 40°F | 23°F | 31.9°F | 2.56 | 10 | <1 | 24 | 10 h 40 min |
| March | 49°F | 30°F | 39.8°F | 4.07 | 11 | <1 | 18 | 11 h 50 min |
| April | 61°F | 40°F | 50.7°F | 3.64 | 13 | <1 | 4 | 13 h 10 min |
| May | 71°F | 50°F | 60.4°F | 3.69 | 13 | 1 | <1 | 14 h 20 min |
| June | 79°F | 59°F | 69.1°F | 3.84 | 13 | 3 | <1 | 15 h |
| July | 84°F | 64°F | 74.0°F | 4.72 | 12 | 8 | <1 | 14 h 50 min |
| August | 82°F | 62°F | 71.9°F | 4.38 | 12 | 4 | <1 | 13 h 50 min |
| September | 75°F | 55°F | 64.7°F | 4.83 | 12 | 1 | <1 | 12 h 30 min |
| October | 63°F | 43°F | 53.3°F | 3.81 | 12 | <1 | 2 | 11 h 10 min |
| November | 52°F | 34°F | 43.0°F | 3.02 | 9 | <1 | 13 | 10 h |
| December | 42°F | 27°F | 34.4°F | 3.76 | 11 | <1 | 23 | 9 h 20 min |
| Year (annual) | 61°F | 43°F | 51.9°F | 45.34 | 137 | 17 | 111 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 3°C | −6°C | −1.3°C | 77 mm |
| February | 5°C | −5°C | −0.1°C | 65 mm |
| March | 10°C | −1°C | 4.3°C | 103 mm |
| April | 16°C | 4°C | 10.4°C | 92 mm |
| May | 22°C | 10°C | 15.8°C | 94 mm |
| June | 26°C | 15°C | 20.6°C | 98 mm |
| July | 29°C | 18°C | 23.3°C | 120 mm |
| August | 28°C | 17°C | 22.2°C | 111 mm |
| September | 24°C | 13°C | 18.2°C | 123 mm |
| October | 17°C | 6°C | 11.8°C | 97 mm |
| November | 11°C | 1°C | 6.1°C | 77 mm |
| December | 6°C | −3°C | 1.3°C | 96 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Graterford (1 mi E) (7 miles away), gets 13 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00054782; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Pottstown?
Normal highs sit between 65°F and 85°F in May, June, July, August and September. Of those, July has the fewest days with rain (12).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00054782.
When is the last frost in Pottstown?
In Pottstown, the last spring frost (32°F) comes after April 20 in half of years and after May 6 in one year in ten; the first autumn frost comes before October 23 in half of years and before October 9 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- April 201 year in 10 after May 6; 9 in 10 after April 5
- First autumn frost, half of years before
- October 231 year in 10 before October 9; 9 in 10 before November 5
NOAA puts the median frost-free season at 186 days, and the season without a hard freeze (28°F) at 212 days.
A hard freeze (28°F) comes after April 6 in half of springs and before November 3 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Pottstown in zone 7a in ZIP code 19464. By the map's own method, the average of each year's coldest night over 1991-2020, Pottstown's NOAA station is in zone 7a: the coldest night of a typical year reaches 4°F (19 complete years).
Frost dates for every NOAA station in Pennsylvania · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00054782; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get in Pottstown?
In a normal year in Pottstown, 17 days a year reach 90°F (1 of them 100°F or more), 111 nights fall to 32°F or colder and 137 days bring measurable precipitation.
- Days at 90°F or more
- 17a normal year
- Days at 100°F or more
- 1a normal year
- Nights at 32°F or colder
- 111a normal year
- Days that stay below freezing
- 20high of 32°F or less
- Days with 0.01 inch of precipitation
- 137a normal year
The highest temperature in this station's record (since 1999) is 105°F, on July 22, 2011; the lowest is −7°F, on January 31, 2019.
The wettest calendar year on that record is 2018, with 71.99 in.
Source: NOAA NCEI 1991-2020 annual normals, station USW00054782; records: ACIS (NOAA Regional Climate Centers), station USW00054782. Records use complete months only; a month missing more than three days is left out.
How sunny is Pottstown?
Over a year 72% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Pottstown, 3.9 kWh per square metre a day. July is the sunniest month (79%) and December the cloudiest (63%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 65% | 1.9 |
| February | 68% | 2.7 |
| March | 67% | 3.6 |
| April | 70% | 4.8 |
| May | 69% | 5.3 |
| June | 74% | 5.9 |
| July | 79% | 6.0 |
| August | 77% | 5.2 |
| September | 75% | 4.2 |
| October | 69% | 3.0 |
| November | 70% | 2.1 |
| December | 63% | 1.6 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Pottstown need?
A normal year in Pottstown brings 5,534 heating degree days, 3% more than the median U.S. place (5,373), and 794 cooling degree days, 13% fewer than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 3,108 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,094 | 0 |
| February | 927 | 0 |
| March | 783 | 0 |
| April | 439 | 9 |
| May | 184 | 43 |
| June | 32 | 155 |
| July | 2 | 281 |
| August | 7 | 219 |
| September | 87 | 78 |
| October | 371 | 9 |
| November | 659 | 0 |
| December | 949 | 0 |
| Year (annual) | 5,534 | 794 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00054782. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Pottstown been warmer than normal lately?
2023 averaged 53.3°F, 1.4°F above the 1991-2020 normal of 51.9°F. 3 of the 3 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 52.9°F | +1.0°F | 42.90 |
| 2022 | 52.0°F | +0.1°F | 46.34 |
| 2023 | 53.3°F | +1.4°F | 41.60 |
Source: observed years: ACIS, station USW00054782. A year counts only with all twelve months complete.
How does Pottstown's climate compare?
Pottstown is warmer than 73 of the other 107 places with their own NOAA record in Pennsylvania, and wetter than 67. Across the 7,247 U.S. stations with normals, its annual mean of 51.9°F is warmer than 49%.
In the Köppen classification computed from these normals, Pottstown is Dfa: continental, no dry season, hot summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Pottstown share this climate record?
16 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Sanatoga, PA9,048 people · 2 mi NW
- Gilbertsville, PA5,999 people · 6 mi NW
- Royersford, PA4,958 people · 4 mi S
- Boyertown, PA4,324 people · 8 mi NW
- Amity Gardens, PA4,158 people · 9 mi W
- Spring City, PA3,925 people · 4 mi S
- Stowe, PA3,645 people · 7 mi W
- Halfway House, PA3,591 people · 5 mi NW
- Pottsgrove, PA3,267 people · 3 mi NW
- South Pottstown, PA2,151 people · 6 mi W
- Kenilworth, PA1,966 people · 4 mi W
- New Berlinville, PA1,745 people · 8 mi NW
- Bally, PA1,234 people · 11 mi N
- Pughtown, PA1,047 people · 7 mi SW
- Bechtelsville, PA887 people · 10 mi NW
- Douglassville, PA322 people · 9 mi W
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Pottstown's climate
What is the coldest month in Pottstown?
January, with a normal high of 37°F and a normal low of 22°F. The warmest is July (84°F by day, 64°F at night).
Does it snow in Pottstown?
Yes. NOAA publishes no 1991-2020 snowfall normal for Pottstown's NOAA station; the nearest record that keeps one, Graterford (1 mi E) (7 miles away), records 13 inches of snow in a normal year.
What is the rainiest month in Pottstown?
September, with 4.83 in of precipitation in a normal year; the driest is February with 2.56 in.
What plant hardiness zone is Pottstown in?
The USDA's 2023 map puts Pottstown in zone 7a in ZIP code 19464. By the same method at Pottstown's NOAA station, the coldest night of a typical year reaches 4°F (19 years, 1991-2020): zone 7a.
How late can frost come in Pottstown?
In half of years the last 32°F night comes after April 20; in one year in ten it comes after May 6. Waiting until May 6 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Pottstown in OctoberThis month day by day, its records and recent years
- Pennsylvania climateThe statewide normals and every place in the state
- Graterford (1 mi E), PA7 miles from this station, 52.4°F a year
- Phoenixville, PA9 miles from this station, 54.4°F a year
- Glenmoore, PA14 miles from this station, 52.5°F a year
- Norristown, PA15 miles from this station, 55.0°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made