Jefferson County (Fairfield)
September
Weather in Jefferson County, Iowa for September 2026
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 21.7 °F. As the month progressed, temperatures tended to significantly warm up, reaching an average of 26.3 °F by the end of September.
With an average of 5 rainy days, Jefferson County experiences minimal rainfall in September.
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Temperatures
Rain 🌧️
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25
Dry days
5
Rainy days
0
Snow days
26°/15°
Temperatures
17 km/h
Avg max wind
71 %
Avg humidity
Jefferson County Weather September
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Temperatures trend during September in Jefferson County
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September weather in Jefferson County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Mist | 25° /14° | 0 mm | 6 | |
| Sept. 2 |  Cloudy | 24° /12° | 0 mm | 5 | |
| Sept. 3 |  Moderate or heavy rain shower | 19° /13° | 61.9 mm | 4 | |
| Sept. 4 | Mist | 21° /6° | 0 mm | 5 | |
| Sept. 5 |  Overcast | 22° /12° | 0 mm | 5 | |
| Sept. 6 | Cloudy | 20° /8° | 0 mm | 5 | |
| Sept. 7 |  Sunny | 21° /4° | 0 mm | 6 | |
| Sept. 8 | Overcast | 24° /12° | 0 mm | 5 | |
| Sept. 9 | Cloudy | 25° /12° | 0 mm | 6 | |
| Sept. 10 |  Light rain shower | 25° /13° | 3.4 mm | 6 | |
| Sept. 11 | Fog | 29° /16° | 0 mm | 6 | |
| Sept. 12 | Overcast | 32° /16° | 0 mm | 7 | |
| Sept. 13 |  Partly cloudy | 35° /20° | 0 mm | 9 | |
| Sept. 14 |  Thundery outbreaks possible | 33° /21° | 0.1 mm | 7 | |
| Sept. 15 | Thundery outbreaks possible | 32° /22° | 0 mm | 7 | |
| Sept. 16 |  Patchy light rain with thunder | 31° /18° | 6.7 mm | 7 | |
| Sept. 17 | Sunny | 31° /16° | 0 mm | 8 | |
| Sept. 18 | Partly cloudy | 31° /17° | 0 mm | 8 | |
| Sept. 19 | Fog | 24° /17° | 9 mm | 5 | |
| Sept. 20 | Moderate or heavy rain shower | 18° /16° | 31.2 mm | 4 | |
| Sept. 21 | Fog | 25° /17° | 0 mm | 6 | |
| Sept. 22 | Patchy rain possible | 24° /16° | 0 mm | 5 | |
| Sept. 23 | Fog | 24° /18° | 0 mm | 5 | |
| Sept. 24 | Overcast | 22° /15° | 0 mm | 5 | |
| Sept. 25 | Mist | 21° /12° | 0 mm | 5 | |
| Sept. 26 | Fog | 27° /12° | 0 mm | 6 | |
| Sept. 27 | Sunny | 28° /13° | 0 mm | 7 | |
| Sept. 28 | Mist | 29° /16° | 0 mm | 6 | |
| Sept. 29 | Partly cloudy | 29° /15° | 0 mm | 7 | |
| Sept. 30 | Overcast | 28° /15° | 0 mm | 6 | |
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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.
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Jefferson County in September - FAQ
What are the expected maximum and minimum temperatures in Jefferson County during September?
During September, expect a variety of temperatures with highs around 26° and lows near 15°, suitable for diverse activities and preferences.
How much rainfall should be expected in Jefferson County during September?
Significant rainfall exceeding 112.3 mm is expected in Jefferson County during September, occurring over more than 5 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Jefferson County during September?
The average wind speed in Jefferson County during September is 17 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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Where is Jefferson County?Get accurate weather forecasts for Jefferson County, located at latitude 41.009 and longitude -91.963. Stay updated with localized weather information tailored for Jefferson County.
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