Illinois Weather Forecast
State weather hub
Mostly Sunny
Compare major city weather across Illinois, scan the latest forecast snapshots, and jump into local 7-day outlook pages from one hub.
Mostly sunny, with a high near 79.
State Weather Overview
This state weather page brings together forecast coverage for Illinois so visitors can compare temperatures, wind, and conditions across the region without hopping between unrelated pages.
Current forecast coverage spans 189 of 189 mapped cities in Illinois.
Page Snapshot
- Page focus
- state weather
- Forecast window
- Aug 23 to Aug 25, 2026
- Latest sync
- Aug 19, 2026 11:54 AM CDT
- Forecast office
- ILX
- Source
- NOAA / NWS
Daily Outlook
This Week in Illinois
Tuesday looks like the warmest upcoming period in Illinois at 83 degrees F.
Sunday Night is the coolest period ahead with temperatures near 61 degrees F.
The strongest winds are forecast for Sunday at about 5 to 8 mph N.
Precipitation is mentioned in 1 upcoming forecast period.
Forecast Details
- Last updated
- Aug 19, 2026 11:54 AM CDT
- Coverage
- 3 days
- Time zone
- America/Chicago
- Forecast office
- ILX
- Radar station
- KILX
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 61.
Mostly sunny, with a high near 80.
Partly cloudy, with a low around 63.
Mostly sunny, with a high near 83.
A slight chance of showers and thunderstorms after 7pm. Partly cloudy, with a low around 65.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Sunday
Aug 23
|
Mostly Sunny
|
79°F |
5 to 8 mph
N
|
|
Sunday Night
Aug 23
|
Partly Cloudy
|
61°F |
3 to 8 mph
ENE
|
|
Monday
Aug 24
|
Mostly Sunny
|
80°F |
7 mph
ESE
|
|
Monday Night
Aug 24
|
Partly Cloudy
|
63°F |
6 mph
ESE
|
|
Tuesday
Aug 25
|
Mostly Sunny
|
83°F |
7 mph
SSE
|
|
Tuesday Night
Aug 25
|
Slight Chance Showers And Thunderstorms
|
65°F |
6 mph
SSE
|
Major City Forecasts
Live forecast snapshots for major cities across Illinois.
Coverage
Forecast coverage currently spans 189 of 189 mapped cities in Illinois.
Largest mapped city population in this region: 2,677,643.
Region Links
