Winnebago County (Rockford)
September
Weather in Winnebago County for September 2025
Your guide to Winnebago County weather in September - trends and predictions
In general, the average temperature in Winnebago County at the beginning of September is 28.6 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 23.9 °F by the end of September.
The climate of Winnebago County in September is notably wet, with an average of 13 rainy days.
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17
Dry days
13
Rainy days
0
Snow days
28°/12°
Temperatures
19 km/h
Avg max wind
68 %
Avg humidity
Winnebago County in September average weather
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| Mon. | Tue. | Wed. | Thu. | Fri. | Sat. | Sun. |
|---|---|---|---|---|---|---|
| 1  27° | 2  30° | 3  32° | 4  32° | 5  32° | 6  26° | 7 21° |
| 8 24° | 9 28° | 10 30° | 11 24° | 12 26° | 13 25° | 14 27° |
| 15 29° | 16 29° | 17 25° | 18 27° | 19  26° | 20  28° | 21 28° |
| 22 24° | 23 25° | 24 22° | 25 25° | 26  25° | 27 22° | 28 23° |
| 29 22° | 30  28° |
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Temperatures trend during September in Winnebago 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 | Sunny | 27° /10° | 0 mm | 7 | |
| Sept. 2 | Mist | 30° /11° | 0 mm | 7 | |
| Sept. 3 | Partly cloudy | 32° /12° | 0 mm | 8 | |
| Sept. 4 | Cloudy | 32° /14° | 0 mm | 7 | |
| Sept. 5 | Overcast | 32° /18° | 1.5 mm | 7 | |
| Sept. 6 | Patchy rain possible | 26° /13° | 2 mm | 6 | |
| Sept. 7 | Patchy rain possible | 21° /7° | 0.2 mm | 6 | |
| Sept. 8 | Mist | 24° /7° | 0 mm | 6 | |
| Sept. 9 | Mist | 28° /8° | 0 mm | 7 | |
| Sept. 10 | Fog | 30° /10° | 0 mm | 7 | |
| Sept. 11 | Light rain shower | 24° /13° | 6.9 mm | 6 | |
| Sept. 12 | Fog | 26° /12° | 0 mm | 6 | |
| Sept. 13 | Mist | 25° /12° | 0 mm | 6 | |
| Sept. 14 | Mist | 27° /10° | 0.1 mm | 6 | |
| Sept. 15 | Mist | 29° /12° | 0 mm | 7 | |
| Sept. 16 | Light rain shower | 29° /15° | 0.8 mm | 7 | |
| Sept. 17 | Light rain shower | 25° /11° | 0.9 mm | 6 | |
| Sept. 18 | Mist | 27° /8° | 0 mm | 6 | |
| Sept. 19 | Moderate or heavy rain with thunder | 26° /11° | 20.8 mm | 6 | |
| Sept. 20 | Patchy light drizzle | 28° /15° | 3.1 mm | 6 | |
| Sept. 21 | Patchy rain possible | 28° /14° | 1.9 mm | 7 | |
| Sept. 22 | Cloudy | 24° /14° | 3.8 mm | 6 | |
| Sept. 23 | Mist | 25° /9° | 0 mm | 6 | |
| Sept. 24 | Patchy light drizzle | 22° /11° | 0.2 mm | 5 | |
| Sept. 25 | Fog | 25° /13° | 2.6 mm | 6 | |
| Sept. 26 | Moderate or heavy rain shower | 25° /11° | 15.4 mm | 6 | |
| Sept. 27 | Light rain shower | 22° /11° | 2.2 mm | 5 | |
| Sept. 28 | Patchy rain possible | 23° /13° | 0 mm | 5 | |
| Sept. 29 | Mist | 22° /12° | 0 mm | 5 | |
| Sept. 30 | Thundery outbreaks possible | 28° /15° | 0 mm | 6 | |
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Important Notice
Our weather forecast for Winnebago 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 Winnebago County forecast closer to your planned date for the most up-to-date weather information.
Winnebago County in September - FAQ
What are the expected maximum and minimum temperatures in Winnebago County during September?
Enjoy moderate daytime temperatures of up to 28° and cooler nights around 12°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Winnebago County during September?
Significant rainfall exceeding 108.7 mm is expected in Winnebago County during September, occurring over more than 13 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Winnebago County during September?
The average wind speed in Winnebago County during September is 19 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Winnebago County
Explore the daily rainfall trends and prepare for Winnebago Countys September weather 💧
UV exposure in Winnebago County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Winnebago County?Get accurate weather forecasts for Winnebago County, located at latitude 42.271 and longitude -89.094. Stay updated with localized weather information tailored for Winnebago County.
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