Illinois (Chicago)
August
Weather in Illinois for August 2027
Your guide to Illinois weather in August - trends and predictions
In general, the average temperature in Illinois at the beginning of August is 26 °C. As the month progressed, temperatures tended to slightly increase, reaching an average of 26.1 °C by the end of August.
The climate of Illinois in August is notably wet, with an average of 12 rainy days, and a total of 152.5 mm of precipitation.
Is August a good time to visit Illinois? check out the best time to travel to Illinois page.
✨ Is August a good time to visit Illinois? – Ask the AI Weatherman
Temperatures
Rain 🌧️
More
19
Dry days
12
Rainy days
0
Snow days
26°/20°
Temperatures
18 km/h
Avg max wind
73 %
Avg humidity
Illinois Weather August
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What’s the Weather Like in Illinois This August?
Discover the average temperatures and weather trends across Illinois’s cities this August.
Temperatures trend during August in Illinois
See the weather trend as well as the moving average line
August weather in Illinois day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Aug. 1 |  Moderate rain | 26° /20° | 15.1 mm | 6 | |
| Aug. 2 |  Cloudy | 26° /20° | 0.8 mm | 7 | |
| Aug. 3 |  Patchy rain possible | 27° /20° | 1.6 mm | 7 | |
| Aug. 4 | Patchy rain possible | 26° /20° | 0.2 mm | 7 | |
| Aug. 5 |  Light rain | 26° /20° | 2.8 mm | 6 | |
| Aug. 6 |  Moderate or heavy rain shower | 25° /20° | 6 mm | 6 | |
| Aug. 7 | Light rain | 27° /20° | 4 mm | 7 | |
| Aug. 8 | Light rain | 27° /21° | 3 mm | 7 | |
| Aug. 9 | Moderate or heavy rain shower | 26° /20° | 5.6 mm | 7 | |
| Aug. 10 | Light rain | 27° /19° | 3.9 mm | 6 | |
| Aug. 11 | Light rain | 27° /21° | 8.2 mm | 6 | |
| Aug. 12 | Moderate rain | 26° /21° | 21.5 mm | 7 | |
| Aug. 13 | Light rain | 25° /20° | 5.9 mm | 7 | |
| Aug. 14 | Light rain | 25° /20° | 5 mm | 7 | |
| Aug. 15 | Light rain | 24° /19° | 6.1 mm | 5 | |
| Aug. 16 | Light rain | 27° /20° | 8.1 mm | 6 | |
| Aug. 17 | Moderate rain | 25° /20° | 11.7 mm | 7 | |
| Aug. 18 | Patchy rain possible | 25° /19° | 1.2 mm | 6 | |
| Aug. 19 | Patchy rain possible | 26° /20° | 0.3 mm | 6 | |
| Aug. 20 | Light rain | 26° /20° | 2.7 mm | 7 | |
| Aug. 21 |  Overcast | 25° /19° | 0.8 mm | 6 | |
| Aug. 22 |  Sunny | 25° /19° | 0.2 mm | 7 | |
| Aug. 23 | Sunny | 28° /19° | 0 mm | 7 | |
| Aug. 24 |  Partly cloudy | 28° /19° | 0.2 mm | 7 | |
| Aug. 25 | Light rain | 26° /19° | 3.4 mm | 6 | |
| Aug. 26 | Patchy rain possible | 26° /19° | 1 mm | 6 | |
| Aug. 27 | Patchy rain possible | 27° /20° | 0.1 mm | 7 | |
| Aug. 28 | Light rain | 26° /20° | 4.8 mm | 7 | |
| Aug. 29 | Patchy rain possible | 26° /20° | 2.2 mm | 6 | |
| Aug. 30 |  Heavy rain | 25° /20° | 26.1 mm | 5 | |
| Aug. 31 | Partly cloudy | 26° /19° | 0.2 mm | 6 | |
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Important Notice
Our weather forecast for Illinois in August 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 Illinois forecast closer to your planned date for the most up-to-date weather information.
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Illinois in August - FAQ
What are the expected maximum and minimum temperatures in Illinois during August?
During August, expect a variety of temperatures with highs around 26° and lows near 20°, suitable for diverse activities and preferences.
How much rainfall should be expected in Illinois during August?
Significant rainfall exceeding 152.5 mm is expected in Illinois during August, occurring over more than 12 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Illinois during August?
The average wind speed in Illinois during August is 18 km/h, suggesting breezy to windy conditions, depending on your activities.
August rainfall patterns in Illinois
Explore the daily rainfall trends and prepare for Illinoiss August weather 💧
Typically, Illinois has 12 rainy days in August with a total of 152.5 mm of rainfall.
UV exposure in Illinois during August
Stay informed about UV levels for safe outdoor activities throughout the month of August ☀️
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