Pennsylvania (Philadelphia)
September
Weather in Pennsylvania for September 2026
Your guide to Pennsylvania weather in September - trends and predictions
So far, September 2026 in Pennsylvania is slightly warmer than the historical average by 0.8 °F.
The forecast for the upcoming days in Pennsylvania predicts a temperature of 18.9 °F, which is slightly above the historical average.
In general, the average temperature in Pennsylvania at the beginning of September is 28.1 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 17.7 °F by the end of September.
Pennsylvania experiences moderate rainfall in September, with an average of 9 rainy days and a total precipitation of 139.3 mm.
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Temperatures
Rain 🌧️
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21
Dry days
9
Rainy days
0
Snow days
25°/17°
Temperatures
15 km/h
Avg max wind
67 %
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 | 28° /19° | 5.7 mm | 6 | |
| Sept. 2 |  Overcast | 27° /17° | 3.7 mm | 6 | |
| Sept. 3 | Sunny | 28° /17° | 47.6 mm | 6 | |
| Sept. 4 | Sunny | 30° /18° | 0.1 mm | 7 | |
| Sept. 5 |  Cloudy | 29° /19° | 4.3 mm | 6 | |
| Sept. 6 | Sunny | 29° /19° | 13.9 mm | 7 | |
| Sept. 7 |  Partly cloudy | 26° /17° | 9.6 mm | 6 | |
| Sept. 8 | Sunny | 28° /16° | 1.2 mm | 7 | |
| Sept. 9 | Sunny | 27° /17° | 2 mm | 6 | |
| Sept. 10 | Sunny | 28° /17° | 0.2 mm | 6 | |
| Sept. 11 | Sunny | 28° /18° | 5.7 mm | 6 | |
| Sept. 12 | Sunny | 29° /18° | 2.7 mm | 7 | |
| Sept. 13 | Sunny | 28° /19° | 5.2 mm | 6 | |
| Sept. 14 | Partly cloudy | 28° /17° | 0.1 mm | 7 | |
| Sept. 15 | Overcast | 27° /16° | 1.1 mm | 7 | |
| Sept. 16 | Cloudy | 26° /15° | 0.4 mm | 6 | |
| Sept. 17 |  Patchy rain possible | 25° /17° | 0.3 mm | 6 | |
| Sept. 18 | Overcast | 26° /18° | 2.6 mm | 6 | |
| Sept. 19 | Sunny | 27° /17° | 6 mm | 6 | |
| Sept. 20 | Sunny | 25° /16° | 3.2 mm | 5 | |
| Sept. 21 | Light rain shower | 21° /14° | 11.5 mm | 5.5 | |
| Sept. 22 | Light rain shower | 15° /12° | 29 mm | 0.6 | |
| Sept. 23 | Light rain shower | 16° /10° | 14.7 mm | 3.9 | |
| Sept. 24 | Overcast | 15° /11° | 3.6 mm | 2.8 | |
| Sept. 25 | Overcast | 20° /10° | 0.7 mm | 4 | |
| Sept. 26 | Light rain shower | 12° /11° | 8.9 mm | 3 | |
| Sept. 27 | Overcast | 17° /12° | 0.5 mm | 5 | |
| Sept. 28 | Overcast | 17° /14° | 0.8 mm | 4 | |
| Sept. 29 | Patchy rain possible | 20° /15° | 4.8 mm | 4 | |
| Sept. 30 | Patchy rain possible | 23° /17° | 1.4 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 139.3 mm is expected in Pennsylvania during September, occurring over more than 9 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 💧
Typically, Pennsylvania has 9 rainy days in September with a total of 139.3 mm of rainfall.
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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