Prince William County (Haymarket)
September
Weather in Prince William County, Virginia for September 2026
Your guide to Prince William County weather in September - trends and predictions
In general, the average temperature in Prince William County at the beginning of September is 26.9 °C. As the month progressed, temperatures tended to noticeably cool down, reaching an average of 24.4 °C by the end of September.
Prince William County experiences moderate rainfall in September, with an average of 10 rainy days and a total precipitation of 224 mm.
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Temperatures
Rain 🌧️
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20
Dry days
10
Rainy days
0
Snow days
25°/17°
Temperatures
12 km/h
Avg max wind
70 %
Avg humidity
Prince William County Weather September
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Temperatures trend during September in Prince William County
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September weather in Prince William County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Overcast | 24° /14° | 0 mm | 9 | |
| Sept. 2 | Overcast | 24° /15° | 0 mm | 7 | |
| Sept. 3 |  Cloudy | 24° /16° | 0 mm | 8 | |
| Sept. 4 | Cloudy | 30° /18° | 4.3 mm | 9 | |
| Sept. 5 |  Mist | 32° /19° | 0 mm | 9 | |
| Sept. 6 |  Moderate or heavy rain shower | 32° /22° | 29.6 mm | 8 | |
| Sept. 7 | Overcast | 22° /17° | 11.4 mm | 4 | |
| Sept. 8 |  Sunny | 23° /13° | 0 mm | 8 | |
| Sept. 9 |  Partly cloudy | 24° /13° | 0 mm | 8 | |
| Sept. 10 | Overcast | 22° /15° | 0 mm | 4 | |
| Sept. 11 | Cloudy | 25° /15° | 0 mm | 7 | |
| Sept. 12 | Sunny | 28° /16° | 0 mm | 7 | |
| Sept. 13 | Sunny | 28° /15° | 0 mm | 7 | |
| Sept. 14 | Partly cloudy | 29° /18° | 0 mm | 7 | |
| Sept. 15 | Cloudy | 28° /19° | 0 mm | 7 | |
| Sept. 16 | Overcast | 21° /17° | 0 mm | 4 | |
| Sept. 17 | Moderate or heavy rain shower | 16° /14° | 60.9 mm | 1 | |
| Sept. 18 | Mist | 28° /17° | 0 mm | 5 | |
| Sept. 19 | Sunny | 31° /18° | 0.3 mm | 6 | |
| Sept. 20 |  Light rain shower | 21° /17° | 51.6 mm | 2 | |
| Sept. 21 | Overcast | 22° /17° | 0 mm | 2 | |
| Sept. 22 | Cloudy | 27° /15° | 0 mm | 6 | |
| Sept. 23 |  Thundery outbreaks possible | 30° /19° | 26.3 mm | 6 | |
| Sept. 24 | Partly cloudy | 27° /19° | 0 mm | 6 | |
| Sept. 25 | Moderate or heavy rain shower | 28° /19° | 23.4 mm | 1 | |
| Sept. 26 | Mist | 23° /20° | 0 mm | 2 | |
| Sept. 27 | Overcast | 24° /18° | 0 mm | 3 | |
| Sept. 28 | Mist | 18° /16° | 12.6 mm | 1 | |
| Sept. 29 | Fog | 26° /16° | 0 mm | 2 | |
| Sept. 30 | Overcast | 25° /18° | 3.6 mm | 1 | |
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Important Notice
Our weather forecast for Prince William 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 Prince William County forecast closer to your planned date for the most up-to-date weather information.
Change Month
Prince William County in September - FAQ
What are the expected maximum and minimum temperatures in Prince William 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 Prince William County during September?
Significant rainfall exceeding 224 mm is expected in Prince William County during September, occurring over more than 10 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Prince William County during September?
The average wind speed in Prince William County during September is 12 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Prince William County
Explore the daily rainfall trends and prepare for Prince William Countys September weather 💧
Typically, Prince William County has 10 rainy days in September with a total of 224 mm of rainfall.
UV exposure in Prince William County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Prince William County?Get accurate weather forecasts for Prince William County, located at latitude 38.812 and longitude -77.636. Stay updated with localized weather information tailored for Prince William County.
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