Cook County (Chicago)
Today
Today weather in Cook County
Sunday, September 20th, 2026
21°
Moderate or heavy rain shower
Feels like 23° · Low 16°
Official weather alert: Flood Advisory. Mild temperatures are expected in Cook County Today, peaking at around 20 °F and dropping to 15 °F by night. It'll be quite breezy in Cook County Today with average wind speeds of 20 km/h. Torrential rain is predicted with a total of over 58.93 mm. Stay safe!
21° / 16°
Temp
93%
Rain
20 km/h
Wind
95%
Humidity
Cook County Weather Pages
Cook County hourly forecast for today
Scroll right to see more weather forecasts for Cook County today
| 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 | 20.5° | 20° | 19.6° | 19.2° | 18.7° | 18.6° | 18.3° | Sunrise | 18.1° | 17.8° | 17.8° | 17.8° | 17.7° | 17.6° | 17.4° | 17.3° | 16.8° | 16.5° | 16° | 15.9° | Sunset | 15.6° | 15.5° | 15.5° | 15.6° | 15.8° | |
| Feels like | 22.9° | 22.7° | 22.1° | 21.5° | 20.6° | 20° | 19.6° | 18.7° | 18.1° | 18.5° | 18.6° | 18.3° | 18° | 17.5° | 17.1° | 15.9° | 15.1° | 14.1° | 13.9° | 13° | 13° | 13.2° | 13.1° | 13.2° | |||
| wind speed | 7 km/h | 4 km/h | 4 km/h | 5 km/h | 6 km/h | 8 km/h | 8 km/h | 11 km/h | 12 km/h | 10 km/h | 9 km/h | 10 km/h | 11 km/h | 12 km/h | 13 km/h | 16 km/h | 17 km/h | 19 km/h | 18 km/h | 21 km/h | 19 km/h | 18 km/h | 18 km/h | 18 km/h | |||
| wind degree | 174° | 180° | 156° | 319° | 18° | 12° | 38° | 54° | 55° | 72° | 54° | 41° | 39° | 31° | 33° | 39° | 42° | 42° | 46° | 54° | 57° | 59° | 64° | 67° | |||
| wind direction | S | S | SSE | NW | NNE | NNE | NE | NE | NE | ENE | NE | NE | NE | NNE | NNE | NE | NE | NE | NE | NE | ENE | ENE | ENE | ENE | |||
| Precipitation | 0.6 mm | 0.4 mm | 1 mm | 11.1 mm | 1.6 mm | 9.1 mm | 3.1 mm | 5 mm | 2.8 mm | 3.7 mm | 3 mm | 2.7 mm | 6 mm | 3.9 mm | 2.1 mm | 1.4 mm | 1.5 mm | 0.1 mm | 0 mm | 0 mm | 0 mm | 0 mm | 0 mm | 0 mm | |||
| chance for rain | 65% | 53% | 76% | 96% | 81% | 94% | 88% | 92% | 87% | 89% | 88% | 87% | 92% | 89% | 83% | 79% | 79% | 45% | 33% | 32% | 31% | 28% | 27% | 26% | |||
| 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% | 98% | 99% | 99% | 98% | 98% | 98% | 99% | 98% | 98% | 98% | 98% | 97% | 97% | 96% | 95% | 94% | 92% | 90% | 88% | 86% | 83% | |||
| dew point | 20° | 19.5° | 19.1° | 18.8° | 18.5° | 18.3° | 18° | 17.8° | 17.5° | 17.6° | 17.5° | 17.4° | 17.3° | 17.1° | 16.9° | 16.3° | 15.9° | 15.2° | 14.9° | 14.3° | 14° | 13.6° | 13.2° | 13° | |||
| visibility | 10 km | 10 km | 10 km | 3 km | 10 km | 5 km | 7 km | 7 km | 7 km | 7 km | 7 km | 7 km | 7 km | 7 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | 10 km | |||
| cloud cover | 87% | 79% | 100% | 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 | 0.1 | 0.5 | 0.7 | 1.1 | 1.8 | 0.9 | 0.8 | 0.5 | 0.4 | 0.3 | 0.1 | 0 | 0 | 0 | 0 | 0 |
View of Cook County today
Explore Cook County live webcam feed to see how the weather is shaping up today in Cook County. 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 Cook County today.
Weather in Cook County today
The weather in Cook County today is expected to be much cooler than usual, with a forecast temperature of 21 °F, compared to an average of 26.8 °F for September 20th in recent years.
temperatures
21 °F
rain
58.9 mm
wind
20 km/h
UV
Low
🌫️ Air quality, UV & pollen - Cook County Live AQI, UV index and pollen levels. Air Quality →
Cook County Today Weather Indexes for Outdoor Activities & Health
Live indexes for outdoor activities, pollen allergies, air quality (AQI), UV index and health in Cook County - Sunday, September 20th, 2026
UV Sun Exposure Risk
Low
2 / 11+
Air Quality Index (AQI)
Excellent
10 / 10
Pollen Allergy Risk
High
8 / 10
Asthma Risk Index
Low
4 / 10
Arthritis Pain Index
Low
3 / 10
Outdoor Activity Index
Good
7 / 10
Running & Jogging Index
Good
6 / 10
Cycling Weather Index
Fair
4 / 10
Pet Walking Index
Excellent
9 / 10
Fishing Conditions Index
Excellent
8 / 10
Gardening Weather Index
Excellent
9 / 10
Photography Light Index
Poor
2 / 10
Driving & Road Safety
Good
6 / 10
Construction Work Index
Excellent
8 / 10
Cook County daylight overview ☀️
Today in Cook County, The sun rises at 06:36 and sets at 18:52, giving a total daylight duration of 12 hours and 16 minutes.
Top locations in Cook County
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What to wear today in Cook County? clothing recommendations
Stay comfortably stylish - your tailored guide for today's Cook County forecast.
Long-sleeve shirt
Long pant
Closed-toe shoes
Light jacket
Umbrella
The weather today in Cook County - FAQ
What is the maximum temperature for today in Cook County?
The maximum temperature for today in Cook County is expected to be 21° degrees. Please dress accordingly to stay comfortable throughout the day.
Will it rain today in Cook County? 🌧️
Yes, there is a 93% chance of rain in Cook County today. We recommend carrying an umbrella or rain gear to stay dry.
What will be the wind speed today in Cook County? 🌀
The wind in Cook County is expected to blow at 20 km/h. This could affect outdoor activities, so plan accordingly.
How should I dress for the weather in Cook County today?
Given the forecast of 21 °F with a 93% 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 Cook County today.
What is the sunrise and sunset time for Cook County today?
The sun is expected to rise at 06:36 and set at 18:52 in Cook County.
How accurate is the weather forecast Cook County today? ✅
Cook County 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 Cook County?Get accurate weather forecasts for Cook County, located at latitude 41.85 and longitude -87.65. Stay updated with localized weather information tailored for Cook County.
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