Illinois (Chicago)
October
Weather in Illinois for October 2025
Your guide to Illinois weather in October - trends and predictions
In general, the average temperature in Illinois at the beginning of October is 21.3 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 14.9 °F by the end of October.
Illinois in October brings notable rainfall, with an average of 16 rainy days and a total precipitation of 120.3 mm.
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Temperatures
Rain 🌧️
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15
Dry days
16
Rainy days
0
Snow days
17°/11°
Temperatures
23 km/h
Avg max wind
63 %
Avg humidity
Illinois in October average weather
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| Mon. | Tue. | Wed. | Thu. | Fri. | Sat. | Sun. |
|---|---|---|---|---|---|---|
| 1  22° | 2  22° | 3  23° | 4  22° | 5  23° | ||
| 6  21° | 7 16° | 8 18° | 9 20° | 10 20° | 11 22° | 12 19° |
| 13 16° | 14 15° | 15 13° | 16 14° | 17 15° | 18 18° | 19 16° |
| 20 19° | 21 20° | 22  17° | 23 18° | 24 18° | 25  17° | 26 15° |
| 27 16° | 28 14° | 29 16° | 30 14° | 31 12° |
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Temperatures trend during October in Illinois
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October weather day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Oct. 1 | Fog | 22° /15° | 0 mm | 5 | |
| Oct. 2 | Sunny | 22° /15° | 0.9 mm | 6 | |
| Oct. 3 | Partly cloudy | 23° /15° | 4.6 mm | 6 | |
| Oct. 4 | Moderate rain at times | 22° /16° | 3.3 mm | 5 | |
| Oct. 5 | Cloudy | 23° /15° | 10.1 mm | 5 | |
| Oct. 6 | Patchy rain possible | 21° /13° | 0.7 mm | 5 | |
| Oct. 7 | Moderate or heavy rain shower | 16° /10° | 3.7 mm | 4 | |
| Oct. 8 | Patchy rain possible | 18° /10° | 0.5 mm | 5 | |
| Oct. 9 | Patchy rain possible | 20° /11° | 0.1 mm | 5 | |
| Oct. 10 | Sunny | 20° /13° | 0 mm | 6 | |
| Oct. 11 | Moderate or heavy rain shower | 22° /13° | 8.9 mm | 5 | |
| Oct. 12 | Moderate or heavy rain shower | 19° /13° | 7.5 mm | 4 | |
| Oct. 13 | Moderate or heavy rain shower | 16° /11° | 16.6 mm | 4 | |
| Oct. 14 | Moderate or heavy rain shower | 15° /10° | 11.8 mm | 3 | |
| Oct. 15 | Moderate rain at times | 13° /8° | 9.2 mm | 3 | |
| Oct. 16 | Cloudy | 14° /7° | 0.2 mm | 4 | |
| Oct. 17 | Partly cloudy | 15° /5° | 0.3 mm | 4 | |
| Oct. 18 | Sunny | 18° /6° | 0 mm | 5 | |
| Oct. 19 | Sunny | 16° /9° | 0.8 mm | 4 | |
| Oct. 20 | Sunny | 19° /9° | 0.3 mm | 5 | |
| Oct. 21 | Patchy rain possible | 20° /10° | 0.7 mm | 5 | |
| Oct. 22 | Overcast | 17° /10° | 0 mm | 4 | |
| Oct. 23 | Partly cloudy | 18° /10° | 0 mm | 5 | |
| Oct. 24 | Moderate or heavy rain shower | 18° /11° | 10.4 mm | 5 | |
| Oct. 25 | Heavy rain at times | 17° /11° | 15.3 mm | 4 | |
| Oct. 26 | Overcast | 15° /11° | 1.2 mm | 4 | |
| Oct. 27 | Partly cloudy | 16° /9° | 1.5 mm | 4 | |
| Oct. 28 | Overcast | 14° /7° | 3.5 mm | 4 | |
| Oct. 29 | Moderate rain at times | 16° /10° | 5.4 mm | 4 | |
| Oct. 30 | Overcast | 14° /9° | 0.6 mm | 4 | |
| Oct. 31 | Sunny | 12° /7° | 2.2 mm | 3 | |
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Important Notice
Our weather forecast for Illinois in October 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.
Illinois in October - FAQ
What are the expected maximum and minimum temperatures in Illinois during October?
Enjoy moderate daytime temperatures of up to 17° and cooler nights around 11°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Illinois during October?
Significant rainfall exceeding 120.3 mm is expected in Illinois during October, occurring over more than 16 days. Preparing for wet conditions is recommended in your planning.
Will it snow in Illinois in October 2025?
Illinois typically sees 0.0275 cm of snowfall during October.
What are the typical wind conditions in Illinois during October?
The average wind speed in Illinois during October is 23 km/h, suggesting breezy to windy conditions, depending on your activities.
October rainfall patterns in Illinois
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UV exposure in Illinois during October
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