Cook County, IL Weather Forecast
County weather hub
Mostly Sunny
Compare major city weather across Cook County, scan the latest forecast snapshots, and jump into local 7-day outlook pages from one hub.
Mostly sunny, with a high near 75.
County Weather Overview
This county weather page brings together forecast coverage for Cook County so visitors can compare temperatures, wind, and conditions across the region without hopping between unrelated pages.
Current forecast coverage spans 27 of 27 mapped cities in Cook County.
Page Snapshot
- Page focus
- county weather
- Forecast window
- Aug 24 to Aug 27, 2026
- Latest sync
- Aug 21, 2026 2:35 AM CDT
- Forecast office
- LOT
- Source
- NOAA / NWS
Daily Outlook
This Week in Cook County
Wednesday looks like the warmest upcoming period in Cook County at 80 degrees F.
Monday Night is the coolest period ahead with temperatures near 62 degrees F.
The strongest winds are forecast for Tuesday at about 5 to 10 mph SSW.
Precipitation is mentioned in 3 upcoming forecast periods.
Forecast Details
- Last updated
- Aug 21, 2026 2:35 AM CDT
- Coverage
- 4 days
- Time zone
- America/Chicago
- Forecast office
- LOT
- Radar station
- KLOT
Weather data is provided by the National Weather Service and refreshed automatically for U.S. locations.
Open NOAA sourceExtended Forecast
Partly cloudy, with a low around 62.
Mostly sunny, with a high near 79.
A chance of showers and thunderstorms after 7pm. Mostly cloudy, with a low around 66.
A chance of rain showers before 1pm, then a slight chance of showers and thunderstorms. Partly sunny, with a high near 80.
A slight chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 66.
Mostly sunny, with a high near 78.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Monday
Aug 24
|
Mostly Sunny
|
75°F |
0 to 5 mph
N
|
|
Monday Night
Aug 24
|
Partly Cloudy
|
62°F |
5 mph
SE
|
|
Tuesday
Aug 25
|
Mostly Sunny
|
79°F |
5 to 10 mph
SSW
|
|
Tuesday Night
Aug 25
|
Chance Showers And Thunderstorms
|
66°F |
5 mph
SW
|
|
Wednesday
Aug 26
|
Chance Rain Showers then Slight Chance Showers And Thunderstorms
|
80°F |
5 to 10 mph
W
|
|
Wednesday Night
Aug 26
|
Slight Chance Showers And Thunderstorms
|
66°F |
5 mph
NW
|
|
Thursday
Aug 27
|
Mostly Sunny
|
78°F |
5 to 10 mph
NNW
|
Major City Forecasts
Live forecast snapshots for major cities across Cook County.
Coverage
Forecast coverage currently spans 27 of 27 mapped cities in Cook County.
Largest mapped city population in this region: 72,683.
