Philadelphia County (Philadelphia)
September
Weather in Philadelphia County, Pennsylvania for September 2026
Your guide to Philadelphia County weather in September - trends and predictions
So far, September 2026 in Philadelphia County is slightly warmer than the historical average by 0.8 °F.
The forecast for the upcoming days in Philadelphia County predicts a temperature of 18.9 °F, which is slightly above the historical average.
In general, the average temperature in Philadelphia County 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.
Philadelphia County 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
Philadelphia County Weather September
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Temperatures trend during September in Philadelphia County
See the weather trend as well as the moving average line
September weather in Philadelphia County 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 Philadelphia County 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 Philadelphia County forecast closer to your planned date for the most up-to-date weather information.
Change Month
Philadelphia County in September - FAQ
What are the expected maximum and minimum temperatures in Philadelphia County 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 Philadelphia County during September?
Significant rainfall exceeding 139.3 mm is expected in Philadelphia County during September, occurring over more than 9 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Philadelphia County during September?
The average wind speed in Philadelphia County during September is 15 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Philadelphia County
Explore the daily rainfall trends and prepare for Philadelphia Countys September weather 💧
Typically, Philadelphia County has 9 rainy days in September with a total of 139.3 mm of rainfall.
UV exposure in Philadelphia County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Philadelphia County?Get accurate weather forecasts for Philadelphia County, located at latitude 39.952 and longitude -75.164. Stay updated with localized weather information tailored for Philadelphia County.
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