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Weather in Jefferson County for September 2025

Your guide to Jefferson County weather in September - trends and predictions
  • In general, the average temperature in Jefferson County at the beginning of September is 29.9 °F. As the month progressed, temperatures tended to moderately fall, reaching an average of 28.6 °F by the end of September.

  • With an average of 3 rainy days, Jefferson County experiences minimal rainfall in September.

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Average dry days
27
Dry days
Average rainy days
3
Rainy days
Average snowy days
0
Snow days
Average temperatures
27°/11°
Temperatures
Average wind speed
15 km/h
Avg max wind
Average humidity
35 %
Avg humidity

Jefferson County in September average weather

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Temperatures trend during September in Jefferson County

See the weather trend as well as the moving average line

September weather day by day

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Date Weather Temperatures Rain UV More
Sept. 1 Cloudy
Cloudy
32° /16° 0 mm 8
Sept. 2 Cloudy
Cloudy
32° /17° 0 mm 8
Sept. 3 Cloudy
Cloudy
32° /18° 1.2 mm 7
Sept. 4 Partly cloudy
Partly cloudy
30° /16° 3.6 mm 7
Sept. 5 Partly cloudy
Partly cloudy
24° /13° 0.5 mm 6
Sept. 6 Sunny
Sunny
29° /13° 0 mm 8
Sept. 7 Sunny
Sunny
30° /14° 0 mm 8
Sept. 8 Sunny
Sunny
31° /16° 0 mm 8
Sept. 9 Partly cloudy
Partly cloudy
31° /15° 0.1 mm 8
Sept. 10 Patchy light rain with thunder
Patchy light rain with thunder
26° /16° 1.2 mm 6
Sept. 11 Thundery outbreaks possible
Thundery outbreaks possible
25° /14° 2.9 mm 6
Sept. 12 Sunny
Sunny
27° /13° 0 mm 7
Sept. 13 Overcast
Overcast
26° /13° 0 mm 7
Sept. 14 Overcast
Overcast
26° /13° 0 mm 6
Sept. 15 Partly cloudy
Partly cloudy
26° /13° 0.1 mm 6
Sept. 16 Partly cloudy
Partly cloudy
26° /10° 0.1 mm 6
Sept. 17 Cloudy
Cloudy
27° /11° 0 mm 6
Sept. 18 Cloudy
Cloudy
27° /10° 0.1 mm 7
Sept. 19 Overcast
Overcast
24° /11° 0 mm 6
Sept. 20 Patchy rain possible
Patchy rain possible
27° /11° 0.1 mm 6
Sept. 21 Patchy rain possible
Patchy rain possible
22° /9° 9.2 mm 5
Sept. 22 Sunny
Sunny
19° /7° 27.4 mm 5
Sept. 23 Overcast
Overcast
25° /6° 0 mm 6
Sept. 24 Partly cloudy
Partly cloudy
24° /11° 0 mm 7
Sept. 25 Sunny
Sunny
28° /9° 0 mm 7
Sept. 26 Sunny
Sunny
30° /11° 0 mm 8
Sept. 27 Sunny
Sunny
29° /15° 0 mm 7
Sept. 28 Partly cloudy
Partly cloudy
31° /11° 0 mm 8
Sept. 29 Sunny
Sunny
30° /12° 0 mm 8
Sept. 30 Partly cloudy
Partly cloudy
28° /11° 0 mm 7
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Important Notice
Our weather forecast for Jefferson 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 Jefferson County forecast closer to your planned date for the most up-to-date weather information.

Jefferson County in September - FAQ

What are the expected maximum and minimum temperatures in Jefferson County during September?
Enjoy moderate daytime temperatures of up to 27° and cooler nights around 11°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Jefferson County during September?
Rainfall in Jefferson County during September is rare to nonexistent, with the total expected rainfall being less than 10 mm and approximately 3 days seeing any precipitation. Planning without the concern for rain is generally straightforward during this very dry period.
What are the typical wind conditions in Jefferson County during September?
The average wind speed in Jefferson County during September is 15 km/h, suggesting breezy to windy conditions, depending on your activities.

September rainfall patterns in Jefferson County

Explore the daily rainfall trends and prepare for Jefferson Countys September weather 💧

UV exposure in Jefferson County during September

Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Location coordinates Where is Jefferson County?

Get accurate weather forecasts for Jefferson County, located at latitude 39.705 and longitude -105.081. Stay updated with localized weather information tailored for Jefferson County.

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