Illinois (Chicago)
Today
Today weather in Illinois
Thursday, September 17th, 2026
21°
Patchy rain possible
Low 18°
Official weather alert: Flood Advisory. Illinois will experience a pleasantly warm today, reaching temperatures of up to 21 °F and cooling to about 18 °F in the evening. It'll be quite breezy in Illinois Today with average wind speeds of 19 km/h. Rain is highly likely at 81%, but with light accumulations around 3.22 mm.
21° / 18°
Temp
81%
Rain
19 km/h
Wind
88%
Humidity
Illinois Weather Pages
Illinois hourly forecast for today
Scroll right to see more weather forecasts for Illinois today
| 12:00 AM | 01:00 AM | 02:00 AM | 03:00 AM | 04:00 AM | 05:00 AM | 06:00 AM | 06:32 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 | 06:57 PM | 07:00 PM | 08:00 PM | 09:00 PM | 10:00 PM | 11:00 PM | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| weather |  | | |  | | | |  | |  | | | |  | |  | | |  | |  | | | |  | | Next |
| temperatures | 19.8° | 19.9° | 19.9° | 19.9° | 18.9° | 18.8° | 18.6° | Sunrise | 18.5° | 18.6° | 18.8° | 19.5° | 19.5° | 18.9° | 20.7° | 21.2° | 21.2° | 20.6° | 19.9° | 19.1° | Sunset | 18.8° | 18.7° | 18.6° | 18.2° | 18.4° | |
| Feels like | 22.1° | 22.3° | 22.7° | 22.7° | 20.8° | 20.4° | 20° | 19.8° | 19.8° | 19.4° | 20.1° | 19.8° | 19.1° | 21.3° | 21.6° | 21.4° | 20° | 19.1° | 18.5° | 18° | 17.6° | 17.2° | 16.9° | 17.2° | |||
| wind speed | 6 km/h | 5 km/h | 4 km/h | 4 km/h | 2 km/h | 4 km/h | 6 km/h | 6 km/h | 6 km/h | 9 km/h | 8 km/h | 10 km/h | 10 km/h | 9 km/h | 10 km/h | 11 km/h | 15 km/h | 16 km/h | 16 km/h | 17 km/h | 18 km/h | 20 km/h | 19 km/h | 17 km/h | |||
| wind degree | 42° | 51° | 17° | 316° | 298° | 334° | 339° | 339° | 11° | 24° | 35° | 51° | 68° | 58° | 50° | 40° | 28° | 24° | 15° | 11° | 12° | 16° | 19° | 20° | |||
| wind direction | NE | NE | NNE | NW | WNW | NNW | NNW | NNW | NNE | NNE | NE | NE | ENE | ENE | NE | NE | NNE | NNE | NNE | NNE | NNE | NNE | NNE | NNE | |||
| Precipitation | 0 mm | 0.1 mm | 0 mm | 0.2 mm | 0.4 mm | 0.4 mm | 0.7 mm | 0.6 mm | 0 mm | 0.1 mm | 0.2 mm | 0.1 mm | 0 mm | 0.1 mm | 0 mm | 0 mm | 0 mm | 0 mm | 0.1 mm | 0.2 mm | 0.2 mm | 0 mm | 0 mm | 0 mm | |||
| chance for rain | 42% | 52% | 45% | 51% | 45% | 52% | 66% | 64% | 29% | 38% | 41% | 35% | 22% | 25% | 10% | 10% | 18% | 17% | 36% | 42% | 44% | 35% | 27% | 25% | |||
| 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 | 97% | 97% | 97% | 97% | 88% | 89% | 91% | 92% | 89% | 88% | 84% | 82% | 85% | 77% | 76% | 76% | 79% | 82% | 89% | 90% | 91% | 92% | 92% | 89% | |||
| dew point | 19.4° | 19.4° | 19.5° | 19.5° | 16.9° | 17° | 17.2° | 17.1° | 16.8° | 16.7° | 16.7° | 16.5° | 16.3° | 16.7° | 16.9° | 16.9° | 16.9° | 16.7° | 17.2° | 17.1° | 17.2° | 17.3° | 16.8° | 16.6° | |||
| visibility | 0 km | 0 km | 0 km | 10 km | 10 km | 9 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | |||
| cloud cover | 100% | 100% | 100% | 100% | 72% | 87% | 96% | 100% | 100% | 100% | 99% | 100% | 82% | 85% | 24% | 24% | 75% | 59% | 100% | 95% | 99% | 100% | 86% | 81% | |||
| UV | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0.3 | 0.7 | 1 | 3.4 | 5.8 | 5.7 | 5.1 | 3.8 | 2.3 | 1 | 0.3 | 0 | 0 | 0 | 0 | 0 |
View of Illinois today
Explore Illinois live webcam feed to see how the weather is shaping up today in Illinois. See what people are wearing, check out the sky, and get a sense of the atmosphere before you step outside.
Stay informed and make the most of your day with our live weather updates from Illinois today.
Weather in Illinois today
The weather in Illinois today is expected to be noticeably cooler than usual, with a forecast temperature of 21 °F, compared to an average of 24.4 °F for September 17th in recent years.
temperatures
21 °F
rain
3.2 mm
wind
19 km/h
UV
High
🌫️ Air quality, UV & pollen - Illinois Live AQI, UV index and pollen levels. Air Quality →
Illinois Today Weather Indexes for Outdoor Activities & Health
Live indexes for outdoor activities, pollen allergies, air quality (AQI), UV index and health in Illinois - Thursday, September 17th, 2026
UV Sun Exposure Risk
High
6 / 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
Excellent
9 / 10
Running & Jogging Index
Good
6 / 10
Cycling Weather Index
Excellent
10 / 10
Pet Walking Index
Excellent
10 / 10
Fishing Conditions Index
Excellent
8 / 10
Gardening Weather Index
Excellent
9 / 10
Photography Light Index
Fair
4 / 10
Driving & Road Safety
Excellent
9 / 10
Construction Work Index
Excellent
8 / 10
Illinois daylight overview ☀️
Today in Illinois, The sun rises at 06:32 and sets at 18:57, giving a total daylight duration of 12 hours and 25 minutes.
Counties in Illinois
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Top locations in Illinois
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What to wear today in Illinois? clothing recommendations
Stay comfortably stylish - your tailored guide for today's Illinois forecast.
Long-sleeve shirt
Long pant
Closed-toe shoes
Light jacket
Umbrella
The weather today in Illinois - FAQ
What is the maximum temperature for today in Illinois?
The maximum temperature for today in Illinois is expected to be 21° degrees. Please dress accordingly to stay comfortable throughout the day.
Will it rain today in Illinois? 🌧️
Yes, there is a 81% chance of rain in Illinois today. We recommend carrying an umbrella or rain gear to stay dry.
What will be the wind speed today 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 today?
Given the forecast of 21 °F with a 81% chance of rain, we advise checking our "What to wear today" section for recommendations. There, you will find tailored advice to help you stay comfortable and prepared for the weather conditions in Illinois today.
What is the sunrise and sunset time for Illinois today?
The sun is expected to rise at 06:32 and set at 18:57 in Illinois.
How accurate is the weather forecast Illinois today? ✅
Illinois weather forecast for today 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.
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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.
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