Pennsylvania (Philadelphia)
September
Weather in Pennsylvania for September 2025
Your guide to Pennsylvania weather in September - trends and predictions
Rip Current Statement - See hour by hour.
Until now, September 2025 in Pennsylvania is slightly cooler than the historical average by -1.9 °F.
Expect cooler weather in the next days in Pennsylvania with the forecast suggesting a temperature of 24.3 °F, lower than the historical average.
In general, the average temperature in Pennsylvania at the beginning of September is 27.7 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 21.7 °F by the end of September.
Pennsylvania in September brings notable rainfall, with an average of 20 rainy days and a total precipitation of 121.2 mm.
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Temperatures
Rain 🌧️
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10
Dry days
20
Rainy days
0
Snow days
25°/17°
Temperatures
15 km/h
Avg max wind
66 %
Avg humidity
Pennsylvania Weather September
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What’s the Weather Like in Pennsylvania This September?
Discover the average temperatures and weather trends across Pennsylvania’s cities this September.
Temperatures trend during September in Pennsylvania
See the weather trend as well as the moving average line
September weather in Pennsylvania day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Sunny | 27° /18° | 6.4 mm | 6 | |
| Sept. 2 |  Overcast | 27° /17° | 1.7 mm | 7 | |
| Sept. 3 | Sunny | 27° /16° | 0 mm | 6 | |
| Sept. 4 | Sunny | 29° /18° | 0 mm | 7 | |
| Sept. 5 |  Cloudy | 29° /19° | 5.1 mm | 7 | |
| Sept. 6 | Overcast | 29° /20° | 14.6 mm | 6 | |
| Sept. 7 |  Partly cloudy | 26° /18° | 11.5 mm | 6 | |
| Sept. 8 |  Patchy rain possible | 27° /17° | 1.5 mm | 6 | |
| Sept. 9 | Sunny | 27° /16° | 2.4 mm | 6 | |
| Sept. 10 | Sunny | 27° /17° | 0.2 mm | 7 | |
| Sept. 11 | Sunny | 27° /17° | 6.7 mm | 6 | |
| Sept. 12 | Sunny | 29° /18° | 3.2 mm | 7 | |
| Sept. 13 | Sunny | 28° /18° | 3.7 mm | 7 | |
| Sept. 14 | Partly cloudy | 29° /17° | 0.1 mm | 7 | |
| Sept. 15 | Overcast | 27° /18° | 0 mm | 1.2 | |
| Sept. 16 | Patchy rain possible | 18° /17° | 0.2 mm | 1.1 | |
| Sept. 17 | Overcast | 19° /16° | 0 mm | 0.3 | |
| Sept. 18 | Overcast | 28° /17° | 0 mm | 1.5 | |
| Sept. 19 | Sunny | 32° /19° | 0 mm | 0 | |
| Sept. 20 | Sunny | 25° /17° | 0 mm | 6 | |
| Sept. 21 | Sunny | 25° /15° | 0 mm | 5 | |
| Sept. 22 | Sunny | 26° /15° | 0 mm | 6 | |
| Sept. 23 | Sunny | 28° /16° | 0 mm | 6 | |
| Sept. 24 | Patchy rain possible | 24° /18° | 4.9 mm | 5 | |
| Sept. 25 | Patchy rain possible | 25° /20° | 2.1 mm | 5 | |
| Sept. 26 |  Moderate rain | 27° /19° | 7.3 mm | 5 | |
| Sept. 27 |  Heavy rain | 19° /17° | 38 mm | 4 | |
| Sept. 28 | Patchy rain possible | 17° /13° | 2.1 mm | 3 | |
| Sept. 29 | Partly cloudy | 20° /13° | 17.8 mm | 5 | |
| Sept. 30 | Sunny | 20° /14° | 1.7 mm | 5 | |
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Important Notice
Our weather forecast for Pennsylvania in September is based on the analysis of historical data rather than real-time forecast models. While this provides a general overview, weather conditions can change. We recommend that you check the Pennsylvania forecast closer to your planned date for the most up-to-date weather information.
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Pennsylvania in September - FAQ
What are the expected maximum and minimum temperatures in Pennsylvania during September?
During September, expect a variety of temperatures with highs around 25° and lows near 17°, suitable for diverse activities and preferences.
How much rainfall should be expected in Pennsylvania during September?
Significant rainfall exceeding 121.2 mm is expected in Pennsylvania during September, occurring over more than 20 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Pennsylvania during September?
The average wind speed in Pennsylvania during September is 15 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Pennsylvania
Explore the daily rainfall trends and prepare for Pennsylvanias September weather 💧
UV exposure in Pennsylvania during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
Counties in Pennsylvania
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Top locations in Pennsylvania
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Where is Pennsylvania?Get accurate weather forecasts for Pennsylvania, located at latitude 39.952 and longitude -75.164. Stay updated with localized weather information tailored for Pennsylvania.
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