Peoria County (Peoria)
September
Weather in Peoria County, Illinois for September 2026
Your guide to Peoria County weather in September - trends and predictions
So far, September 2026 in Peoria County is slightly warmer than the historical average by 1.1 °F.
The forecast for the next days in Peoria County predicts temperatures to be around 19 °F, close to the historical average.
In general, the average temperature in Peoria County at the beginning of September is 28.7 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 19.7 °F by the end of September.
Peoria County experiences moderate rainfall in September, with an average of 6 rainy days and a total precipitation of 112.9 mm.
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Temperatures
Rain 🌧️
More
24
Dry days
6
Rainy days
0
Snow days
27°/14°
Temperatures
17 km/h
Avg max wind
64 %
Avg humidity
Peoria County Weather September
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Temperatures trend during September in Peoria County
See the weather trend as well as the moving average line
September weather in Peoria County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Sunny | 31° /16° | 0 mm | 7 | |
| Sept. 2 | Sunny | 30° /15° | 0 mm | 7 | |
| Sept. 3 |  Partly cloudy | 31° /15° | 33.2 mm | 7 | |
| Sept. 4 | Sunny | 30° /14° | 0 mm | 7 | |
| Sept. 5 |  Mist | 30° /17° | 0 mm | 7 | |
| Sept. 6 | Partly cloudy | 25° /13° | 0 mm | 6 | |
| Sept. 7 | Sunny | 24° /8° | 0 mm | 6 | |
| Sept. 8 | Sunny | 27° /9° | 0 mm | 6 | |
| Sept. 9 | Sunny | 26° /13° | 18.3 mm | 5 | |
| Sept. 10 | Sunny | 28° /14° | 31.6 mm | 5 | |
| Sept. 11 | Sunny | 31° /15° | 0.1 mm | 7 | |
| Sept. 12 | Sunny | 31° /15° | 0.1 mm | 7 | |
| Sept. 13 |  Overcast | 28° /17° | 0.4 mm | 6 | |
| Sept. 14 |  Patchy rain possible | 31° /16° | 0 mm | 7 | |
| Sept. 15 |  Cloudy | 32° /19° | 1 mm | 5 | |
| Sept. 16 | Sunny | 31° /18° | 4.7 mm | 6 | |
| Sept. 17 | Sunny | 30° /15° | 5.7 mm | 6 | |
| Sept. 18 | Sunny | 29° /15° | 6.1 mm | 6 | |
| Sept. 19 | Partly cloudy | 28° /16° | 1.8 mm | 5 | |
| Sept. 20 | Overcast | 23° /16° | 1.2 mm | 5.8 | |
| Sept. 21 | Patchy rain possible | 19° /14° | 2 mm | 0.6 | |
| Sept. 22 | Patchy rain possible | 15° /13° | 0.6 mm | 0.9 | |
| Sept. 23 | Overcast | 20° /12° | 0.2 mm | 5.7 | |
| Sept. 24 | Overcast | 21° /12° | 0 mm | 5 | |
| Sept. 25 | Patchy rain possible | 20° /14° | 1.5 mm | 5 | |
| Sept. 26 | Overcast | 22° /13° | 0.1 mm | 6 | |
| Sept. 27 | Overcast | 23° /17° | 0 mm | 6 | |
| Sept. 28 | Overcast | 18° /8° | 11.5 mm | 4 | |
| Sept. 29 | Sunny | 14° /6° | 0 mm | 4 | |
| Sept. 30 | Sunny | 20° /10° | 0 mm | 5 | |
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Important Notice
Our weather forecast for Peoria 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 Peoria County forecast closer to your planned date for the most up-to-date weather information.
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Peoria County in September - FAQ
What are the expected maximum and minimum temperatures in Peoria County during September?
Enjoy moderate daytime temperatures of up to 27° and cooler nights around 14°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Peoria County during September?
Significant rainfall exceeding 112.9 mm is expected in Peoria County during September, occurring over more than 6 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Peoria County during September?
The average wind speed in Peoria County during September is 17 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Peoria County
Explore the daily rainfall trends and prepare for Peoria Countys September weather 💧
Typically, Peoria County has 6 rainy days in September with a total of 112.9 mm of rainfall.
UV exposure in Peoria County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Peoria County?Get accurate weather forecasts for Peoria County, located at latitude 40.694 and longitude -89.589. Stay updated with localized weather information tailored for Peoria County.
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