Illinois (Chicago)
Tomorrow
Tomorrow weather in Illinois
Sunday, September 20th, 2026
20°
Light rain shower
Low 16°
The weather tomorrow in Illinois will be similar like today, with max temperatures of 19°.
The rain is expected to get stronger, the expected precipitation are 33 mm.
20° / 16°
Temp
94%
Rain
19 km/h
Wind
97%
Humidity
Illinois Tomorrow's Weather Forecast
Click on a location for more weather information
Illinois Weather Pages
Illinois hourly forecast for tomorrow
Scroll right to see more weather forecasts for Illinois tomorrow
| 12:00 AM | 01:00 AM | 02:00 AM | 03:00 AM | 04:00 AM | 05:00 AM | 06:00 AM | 06:36 AM | 07:00 AM | 08:00 AM | 09:00 AM | 10:00 AM | 11:00 AM | 12:00 PM | 01:00 PM | 02:00 PM | 03:00 PM | 04:00 PM | 05:00 PM | 06:00 PM | 06:52 PM | 07:00 PM | 08:00 PM | 09:00 PM | 10:00 PM | 11:00 PM | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| weather |  | |  |  | | | |  |  | | | | | | | |  | | | |  | | | | | | Next |
| temperatures | 18.9° | 19° | 19° | 18.9° | 19° | 18.8° | 18.7° | Sunrise | 18.5° | 18.4° | 18.1° | 17.8° | 18° | 18.6° | 19.6° | 18.1° | 17.3° | 16.9° | 16.6° | 16° | Sunset | 15.8° | 15.7° | 15.7° | 15.7° | 15.5° | |
| Feels like | 21.6° | 21.4° | 21.9° | 20.9° | 21.3° | 20.8° | 20.5° | 19.7° | 18.9° | 18.2° | 17.8° | 18° | 19.1° | 20.9° | 18.4° | 16.6° | 15.8° | 15.1° | 14.3° | 13.7° | 13.5° | 13.5° | 13.6° | 13.6° | |||
| wind speed | 3 km/h | 4 km/h | 1 km/h | 6 km/h | 5 km/h | 6 km/h | 7 km/h | 9 km/h | 12 km/h | 14 km/h | 13 km/h | 13 km/h | 11 km/h | 9 km/h | 13 km/h | 16 km/h | 17 km/h | 18 km/h | 18 km/h | 19 km/h | 19 km/h | 19 km/h | 18 km/h | 17 km/h | |||
| wind degree | 26° | 48° | 115° | 77° | 21° | 42° | 54° | 42° | 48° | 54° | 74° | 88° | 86° | 58° | 18° | 21° | 38° | 42° | 46° | 58° | 58° | 62° | 68° | 64° | |||
| wind direction | NNE | NE | ESE | ENE | NNE | NE | NE | NE | NE | NE | ENE | E | E | ENE | NNE | NNE | NE | NE | NE | ENE | ENE | ENE | ENE | ENE | |||
| Precipitation | 1.3 mm | 2.2 mm | 2.8 mm | 0.1 mm | 1.1 mm | 0.3 mm | 0.3 mm | 0.1 mm | 0.4 mm | 0.6 mm | 1.1 mm | 1 mm | 0.5 mm | 0.7 mm | 2.4 mm | 6.6 mm | 3.2 mm | 3.8 mm | 3.7 mm | 1.1 mm | 0 mm | 0.2 mm | 0 mm | 0.1 mm | |||
| chance for rain | 80% | 85% | 87% | 49% | 79% | 58% | 59% | 52% | 60% | 67% | 78% | 76% | 66% | 68% | 85% | 92% | 88% | 89% | 88% | 77% | 34% | 47% | 35% | 41% | |||
| chance for snow | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | |||
| humidity | 99% | 100% | 99% | 99% | 99% | 99% | 99% | 98% | 98% | 97% | 98% | 96% | 96% | 94% | 98% | 97% | 97% | 96% | 96% | 96% | 95% | 94% | 93% | 91% | |||
| dew point | 18.8° | 18.9° | 18.8° | 18.8° | 18.9° | 18.7° | 18.6° | 18.3° | 18° | 17.7° | 17.4° | 17.5° | 17.9° | 18.6° | 17.7° | 16.9° | 16.5° | 16.1° | 15.4° | 15.2° | 14.9° | 14.7° | 14.5° | 14.1° | |||
| visibility | 10 km | 10 km | 7 km | 0 km | 10 km | 10 km | 10 km | 0 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 7 km | 7 km | 7 km | 7 km | 10 km | 10 km | 10 km | 10 km | 10 km | |||
| cloud cover | 100% | 100% | 98% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | |||
| UV | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0.3 | 0.9 | 1.1 | 1.5 | 1.6 | 0.6 | 1 | 0.7 | 0.5 | 0.2 | 0.1 | 0 | 0 | 0 | 0 | 0 |
Weather in Illinois tomorrow
The weather in Illinois tomorrow is expected to be much cooler than usual, with a forecast temperature of 20 °F, compared to an average of 26.8 °F for September 20th in recent years.
temperatures
20 °F
rain
33.7 mm
wind
19 km/h
UV
Low
🌫️ Air quality, UV & pollen - Illinois Live AQI, UV index and pollen levels. Air Quality →
Illinois Tomorrow Weather Indexes for Outdoor Activities & Health
Weather indexes for tomorrow: outdoor activities, pollen allergies, air quality (AQI), UV index and health in Illinois - Sunday, September 20th, 2026
UV Sun Exposure Risk
Low
1 / 11+
Air Quality Index (AQI)
Excellent
10 / 10
Pollen Allergy Risk
Very High
10 / 10
Asthma Risk Index
Low
4 / 10
Arthritis Pain Index
Low
3 / 10
Outdoor Activity Index
Good
7 / 10
Running & Jogging Index
Fair
4 / 10
Cycling Weather Index
Fair
4 / 10
Pet Walking Index
Excellent
8 / 10
Fishing Conditions Index
Excellent
10 / 10
Gardening Weather Index
Excellent
10 / 10
Photography Light Index
Fair
4 / 10
Driving & Road Safety
Good
6 / 10
Construction Work Index
Fair
5 / 10
Illinois daylight overview ☀️
Tomorrow in Illinois, The sun rises at 06:36 and sets at 18:52, giving a total daylight duration of 12 hours and 16 minutes.
Counties in Illinois
Select a county for an accurate weather forecast
Top locations in Illinois
Select a location for an accurate weather forecast
More Locations Quick links
More Illinois weather pages
What to wear tomorrow in Illinois? clothing recommendations
Stay comfortably stylish - your tailored guide for tomorrow's Illinois forecast.
Long-sleeve shirt
Long pant
Closed-toe shoes
Light jacket
Umbrella
The weather tomorrow in Illinois - FAQ
What is the maximum temperature for tomorrow in Illinois?
The maximum temperature for tomorrow in Illinois is expected to be 20° degrees. Please dress accordingly to stay comfortable throughout the day.
Will it rain tomorrow in Illinois? 🌧️
Yes, there is a 94% chance of rain in Illinois tomorrow. We recommend carrying an umbrella or rain gear to stay dry.
What will be the wind speed tomorrow in Illinois? 🌀
The wind in Illinois is expected to blow at 19 km/h. This could affect outdoor activities, so plan accordingly.
How should I dress for the weather in Illinois tomorrow?
Given the forecast of 20 °F with a 94% chance of rain, we advise checking our "What to wear tomorrow" section for recommendations. There, you will find tailored advice to help you stay comfortable and prepared for the weather conditions in Illinois tomorrow.
What is the sunrise and sunset time for Illinois tomorrow?
The sun is expected to rise at 06:36 and set at 18:52 in Illinois.
How accurate is the weather forecast Illinois tomorrow? ✅
Illinois weather forecast for tomorrow is based on the most current and sophisticated meteorological models available. While we strive for accuracy, weather conditions can change unexpectedly, so we recommend checking for updates regularly.
You are here
Where is Illinois?Get accurate weather forecasts for Illinois, located at latitude 41.85 and longitude -87.65. Stay updated with localized weather information tailored for Illinois.
Found a mistake?
We appreciate your attention to details. Tell us here.