Joliet (IL)
September
Weather in Joliet, Illinois for September 2025
Your guide to Joliet weather in September - trends and predictions
In general, the average temperature in Joliet at the beginning of September is 29.3 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 24 °F by the end of September.
Joliet experiences moderate rainfall in September, with an average of 9 rainy days and a total precipitation of 62.2 mm.
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Temperatures
Rain 🌧️
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21
Dry days
9
Rainy days
0
Snow days
27°/14°
Temperatures
18 km/h
Avg max wind
65 %
Avg humidity
Joliet Weather September
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Temperatures trend during September in Joliet
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September weather in Joliet day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Sunny | 28° /12° | 0 mm | 7 | |
| Sept. 2 |  Mist | 29° /12° | 0 mm | 7 | |
| Sept. 3 | Fog | 32° /13° | 0 mm | 8 | |
| Sept. 4 | Mist | 34° /15° | 0 mm | 8 | |
| Sept. 5 |  Cloudy | 33° /18° | 1.9 mm | 8 | |
| Sept. 6 |  Patchy rain possible | 27° /15° | 2.4 mm | 6 | |
| Sept. 7 |  Overcast | 22° /10° | 0 mm | 6 | |
| Sept. 8 |  Partly cloudy | 24° /9° | 0 mm | 7 | |
| Sept. 9 | Mist | 27° /11° | 0 mm | 7 | |
| Sept. 10 | Partly cloudy | 29° /12° | 0 mm | 8 | |
| Sept. 11 | Light rain shower | 27° /15° | 16.6 mm | 7 | |
| Sept. 12 | Fog | 28° /13° | 0 mm | 7 | |
| Sept. 13 | Mist | 26° /13° | 0 mm | 6 | |
| Sept. 14 | Mist | 27° /12° | 0 mm | 7 | |
| Sept. 15 | Cloudy | 29° /14° | 0 mm | 7 | |
| Sept. 16 |  Thundery outbreaks possible | 29° /14° | 0.3 mm | 7 | |
| Sept. 17 | Light rain shower | 25° /13° | 2.7 mm | 6 | |
| Sept. 18 | Mist | 27° /10° | 0 mm | 6 | |
| Sept. 19 |  Moderate rain | 27° /12° | 2.7 mm | 6 | |
| Sept. 20 | Fog | 30° /15° | 0 mm | 7 | |
| Sept. 21 | Patchy rain possible | 29° /14° | 1.5 mm | 7 | |
| Sept. 22 | Light rain shower | 25° /16° | 14.8 mm | 6 | |
| Sept. 23 | Mist | 24° /12° | 0 mm | 5 | |
| Sept. 24 | Mist | 23° /11° | 0 mm | 6 | |
| Sept. 25 | Fog | 26° /15° | 0.1 mm | 6 | |
| Sept. 26 |  Moderate or heavy rain shower | 26° /13° | 14.3 mm | 6 | |
| Sept. 27 | Light rain shower | 22° /14° | 5 mm | 5 | |
| Sept. 28 | Fog | 21° /16° | 0 mm | 5 | |
| Sept. 29 | Fog | 23° /16° | 0 mm | 6 | |
| Sept. 30 | Fog | 27° /15° | 0 mm | 6 | |
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Important Notice
Our weather forecast for Joliet 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 Joliet forecast closer to your planned date for the most up-to-date weather information.
Change Month
Joliet in September - FAQ
What are the expected maximum and minimum temperatures in Joliet 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 Joliet during September?
Moderate rainfall is anticipated in Joliet during September, with a total of 62.2 mm spread over approximately 9 days. Considering plans for rainy days is advisable.
What are the typical wind conditions in Joliet during September?
The average wind speed in Joliet during September is 18 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Joliet
Explore the daily rainfall trends and prepare for Joliets September weather 💧
UV exposure in Joliet during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Joliet?Get accurate weather forecasts for Joliet, located at latitude 41.525 and longitude -88.083. Stay updated with localized weather information tailored for Joliet.
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