Loudoun County (Leesburg)
September
Weather in Loudoun County, Virginia for September 2026
Your guide to Loudoun County weather in September - trends and predictions
So far, September 2026 in Loudoun County shows a warmer trend than usual by 3.4 °F.
The forecast for the next days in Loudoun County predicts temperatures to be around 20 °F, close to the historical average.
In general, the average temperature in Loudoun County at the beginning of September is 28.6 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 18.9 °F by the end of September.
Loudoun County in September brings notable rainfall, with an average of 20 rainy days and a total precipitation of 134.5 mm.
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Temperatures
Rain 🌧️
More
10
Dry days
20
Rainy days
0
Snow days
25°/15°
Temperatures
14 km/h
Avg max wind
74 %
Avg humidity
Loudoun County Weather September
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Temperatures trend during September in Loudoun County
See the weather trend as well as the moving average line
September weather in Loudoun County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Moderate or heavy rain shower | 30° /17° | 2.2 mm | 7 | |
| Sept. 2 |  Partly cloudy | 29° /16° | 8.3 mm | 6 | |
| Sept. 3 |  Sunny | 29° /15° | 4.2 mm | 7 | |
| Sept. 4 |  Overcast | 30° /16° | 11.3 mm | 5 | |
| Sept. 5 | Partly cloudy | 28° /16° | 4.1 mm | 6 | |
| Sept. 6 | Overcast | 29° /16° | 5.9 mm | 7 | |
| Sept. 7 |  Heavy rain at times | 25° /14° | 1.2 mm | 6 | |
| Sept. 8 | Sunny | 25° /10° | 0 mm | 6 | |
| Sept. 9 | Sunny | 27° /11° | 0 mm | 6 | |
| Sept. 10 | Sunny | 28° /14° | 0.6 mm | 5 | |
| Sept. 11 | Sunny | 27° /16° | 0.1 mm | 5 | |
| Sept. 12 | Sunny | 27° /14° | 1.2 mm | 5 | |
| Sept. 13 |  Patchy rain possible | 28° /16° | 1.2 mm | 5 | |
| Sept. 14 | Overcast | 28° /16° | 0 mm | 6 | |
| Sept. 15 | Overcast | 27° /13° | 1.3 mm | 7 | |
| Sept. 16 | Overcast | 25° /14° | 0.6 mm | 6 | |
| Sept. 17 | Moderate or heavy rain shower | 23° /16° | 9.8 mm | 5 | |
| Sept. 18 | Moderate or heavy rain shower | 26° /18° | 4.3 mm | 5 | |
| Sept. 19 | Sunny | 27° /16° | 0 mm | 6.6 | |
| Sept. 20 | Patchy rain possible | 28° /18° | 5.3 mm | 4.1 | |
| Sept. 21 | Light rain shower | 21° /16° | 7.6 mm | 2.6 | |
| Sept. 22 | Light rain shower | 18° /14° | 10.2 mm | 4 | |
| Sept. 23 | Light rain shower | 13° /10° | 14.8 mm | 3 | |
| Sept. 24 |  Fog | 14° /13° | 1.9 mm | 3 | |
| Sept. 25 | Mist | 16° /12° | 1.2 mm | 4 | |
| Sept. 26 | Sunny | 21° /11° | 0 mm | 6 | |
| Sept. 27 | Sunny | 21° /10° | 0 mm | 6 | |
| Sept. 28 | Overcast | 17° /12° | 0 mm | 4 | |
| Sept. 29 | Sunny | 22° /13° | 0 mm | 6 | |
| Sept. 30 | Overcast | 21° /12° | 0 mm | 5 | |
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Important Notice
Our weather forecast for Loudoun 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 Loudoun County forecast closer to your planned date for the most up-to-date weather information.
Change Month
Loudoun County in September - FAQ
What are the expected maximum and minimum temperatures in Loudoun County during September?
During September, expect a variety of temperatures with highs around 25° and lows near 15°, suitable for diverse activities and preferences.
How much rainfall should be expected in Loudoun County during September?
Significant rainfall exceeding 134.5 mm is expected in Loudoun County during September, occurring over more than 20 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Loudoun County during September?
The average wind speed in Loudoun County during September is 14 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Loudoun County
Explore the daily rainfall trends and prepare for Loudoun Countys September weather 💧
Typically, Loudoun County has 20 rainy days in September with a total of 134.5 mm of rainfall.
UV exposure in Loudoun County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Loudoun County?Get accurate weather forecasts for Loudoun County, located at latitude 39.116 and longitude -77.564. Stay updated with localized weather information tailored for Loudoun County.
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