Wilmington (DE)
September
Weather in Wilmington, Delaware for September 2026
Your guide to Wilmington weather in September - trends and predictions
In general, the average temperature in Wilmington at the beginning of September is 26.6 °F. As the month progressed, temperatures tended to moderately fall, reaching an average of 24.7 °F by the end of September.
Wilmington experiences moderate rainfall in September, with an average of 8 rainy days and a total precipitation of 219.9 mm.
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Temperatures
Rain 🌧️
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22
Dry days
8
Rainy days
0
Snow days
25°/17°
Temperatures
13 km/h
Avg max wind
72 %
Avg humidity
Wilmington Weather September
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Temperatures trend during September in Wilmington
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September weather in Wilmington day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Overcast | 24° /17° | 0 mm | 4 | |
| Sept. 2 |  Sunny | 27° /17° | 0 mm | 8 | |
| Sept. 3 | Overcast | 23° /16° | 0 mm | 6 | |
| Sept. 4 |  Mist | 29° /16° | 0 mm | 8 | |
| Sept. 5 | Mist | 32° /19° | 22.5 mm | 7 | |
| Sept. 6 |  Light rain shower | 31° /21° | 21.9 mm | 7 | |
| Sept. 7 |  Moderate or heavy rain shower | 20° /14° | 81.6 mm | 4 | |
| Sept. 8 | Sunny | 23° /13° | 0 mm | 8 | |
| Sept. 9 |  Cloudy | 23° /15° | 0 mm | 8 | |
| Sept. 10 | Overcast | 21° /16° | 0 mm | 2 | |
| Sept. 11 |  Partly cloudy | 26° /15° | 0 mm | 7 | |
| Sept. 12 | Partly cloudy | 25° /17° | 0 mm | 7 | |
| Sept. 13 | Mist | 25° /17° | 0 mm | 5 | |
| Sept. 14 | Overcast | 28° /18° | 0 mm | 7 | |
| Sept. 15 | Moderate rain at times | 26° /18° | 3.5 mm | 7 | |
| Sept. 16 | Overcast | 24° /15° | 0 mm | 7 | |
| Sept. 17 | Moderate rain at times | 19° /15° | 3.6 mm | 1 | |
| Sept. 18 | Overcast | 27° /18° | 0 mm | 4 | |
| Sept. 19 | Partly cloudy | 31° /18° | 0 mm | 6 | |
| Sept. 20 | Overcast | 20° /16° | 0 mm | 3 | |
| Sept. 21 | Overcast | 21° /15° | 0 mm | 3 | |
| Sept. 22 | Overcast | 24° /16° | 0 mm | 3 | |
| Sept. 23 | Fog | 28° /18° | 0 mm | 3 | |
| Sept. 24 | Mist | 28° /18° | 0 mm | 4 | |
| Sept. 25 | Light rain shower | 26° /19° | 40.4 mm | 1 | |
| Sept. 26 | Mist | 24° /19° | 5.6 mm | 4 | |
| Sept. 27 | Mist | 25° /16° | 0 mm | 4 | |
| Sept. 28 |  Moderate rain | 20° /17° | 40.8 mm | 1 | |
| Sept. 29 | Fog | 25° /17° | 0 mm | 2 | |
| Sept. 30 | Overcast | 25° /17° | 0 mm | 1 | |
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Important Notice
Our weather forecast for Wilmington 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 Wilmington forecast closer to your planned date for the most up-to-date weather information.
Change Month
Wilmington in September - FAQ
What are the expected maximum and minimum temperatures in Wilmington 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 Wilmington during September?
Significant rainfall exceeding 219.9 mm is expected in Wilmington during September, occurring over more than 8 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Wilmington during September?
The average wind speed in Wilmington during September is 13 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Wilmington
Explore the daily rainfall trends and prepare for Wilmingtons September weather 💧
Typically, Wilmington has 8 rainy days in September with a total of 219.9 mm of rainfall.
UV exposure in Wilmington during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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