Frederick County (Frederick)
September
Weather in Frederick County, Maryland for September 2026
Your guide to Frederick County weather in September - trends and predictions
So far, September 2026 in Frederick County shows a warmer trend than usual by 2.5 °F.
The forecast for the next days in Frederick County predicts temperatures to be around 21 °F, close to the historical average.
In general, the average temperature in Frederick County at the beginning of September is 28 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 21.1 °F by the end of September.
The climate of Frederick County in September is notably wet, with an average of 14 rainy days, and a total of 160.1 mm of precipitation.
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Temperatures
Rain 🌧️
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16
Dry days
14
Rainy days
0
Snow days
24°/14°
Temperatures
15 km/h
Avg max wind
75 %
Avg humidity
Frederick County Weather September
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Temperatures trend during September in Frederick County
See the weather trend as well as the moving average line
September weather in Frederick County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Light rain shower | 30° /17° | 1.2 mm | 7 | |
| Sept. 2 |  Overcast | 28° /16° | 6.9 mm | 5 | |
| Sept. 3 |  Sunny | 28° /14° | 0 mm | 6 | |
| Sept. 4 | Overcast | 29° /15° | 25.9 mm | 4 | |
| Sept. 5 |  Mist | 28° /16° | 2.9 mm | 6 | |
| Sept. 6 | Patchy rain possible | 28° /15° | 2.5 mm | 7 | |
| Sept. 7 |  Patchy light drizzle | 25° /12° | 0.2 mm | 6 | |
| Sept. 8 | Sunny | 25° /9° | 0 mm | 6 | |
| Sept. 9 | Sunny | 27° /11° | 0 mm | 6 | |
| Sept. 10 | Sunny | 28° /13° | 0.5 mm | 5 | |
| Sept. 11 | Sunny | 28° /15° | 2.3 mm | 5 | |
| Sept. 12 | Sunny | 27° /14° | 0.1 mm | 6 | |
| Sept. 13 | Mist | 28° /16° | 1.4 mm | 5 | |
| Sept. 14 | Mist | 27° /15° | 0 mm | 6 | |
| Sept. 15 | Sunny | 27° /12° | 1.9 mm | 7 | |
| Sept. 16 | Overcast | 26° /13° | 1.4 mm | 6 | |
| Sept. 17 | Overcast | 22° /15° | 0.6 mm | 4 | |
| Sept. 18 | Fog | 25° /17° | 0.9 mm | 5 | |
| Sept. 19 | Overcast | 27° /14° | 0.7 mm | 6 | |
| Sept. 20 |  Partly cloudy | 24° /16° | 3.5 mm | 4 | |
| Sept. 21 |  Moderate or heavy rain shower | 22° /16° | 11.5 mm | 4 | |
| Sept. 22 | Light rain shower | 20° /13° | 12.7 mm | 4 | |
| Sept. 23 | Overcast | 18° /10° | 0.9 mm | 5.8 | |
| Sept. 24 | Sunny | 18° /8° | 0 mm | 5.4 | |
| Sept. 25 | Sunny | 21° /8° | 0 mm | 5.6 | |
| Sept. 26 | Sunny | 22° /9° | 0 mm | 5.5 | |
| Sept. 27 | Sunny | 23° /9° | 0 mm | 6 | |
| Sept. 28 | Sunny | 24° /11° | 0 mm | 6 | |
| Sept. 29 | Overcast | 21° /14° | 0 mm | 5 | |
| Sept. 30 | Patchy rain possible | 19° /16° | 5.5 mm | 4 | |
| Next | |||||
Important Notice
Our weather forecast for Frederick 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 Frederick County forecast closer to your planned date for the most up-to-date weather information.
Change Month
Frederick County in September - FAQ
What are the expected maximum and minimum temperatures in Frederick County during September?
Enjoy moderate daytime temperatures of up to 24° and cooler nights around 14°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Frederick County during September?
Significant rainfall exceeding 160.1 mm is expected in Frederick County during September, occurring over more than 14 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Frederick County during September?
The average wind speed in Frederick County during September is 15 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Frederick County
Explore the daily rainfall trends and prepare for Frederick Countys September weather 💧
Typically, Frederick County has 14 rainy days in September with a total of 160.1 mm of rainfall.
UV exposure in Frederick County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Frederick County?Get accurate weather forecasts for Frederick County, located at latitude 39.414 and longitude -77.411. Stay updated with localized weather information tailored for Frederick County.
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