Saint Clair County, IL Weather Forecast
County weather hub
Showers And Thunderstorms Likely
Compare major city weather across Saint Clair County, scan the latest forecast snapshots, and jump into local 7-day outlook pages from one hub.
A chance of rain showers before 7am, then showers and thunderstorms likely. Partly sunny, with a high near 82. Chance of precipitation is 60%.
County Weather Overview
This county weather page brings together forecast coverage for Saint Clair County so visitors can compare temperatures, wind, and conditions across the region without hopping between unrelated pages.
Current forecast coverage spans 15 of 15 mapped cities in Saint Clair County.
Page Snapshot
- Page focus
- county weather
- Forecast window
- May 26 to May 28, 2026
- Latest sync
- May 21, 2026 9:44 PM CDT
- Forecast office
- LSX
- Source
- NOAA / NWS
Daily Outlook
This Week in Saint Clair County
Thursday looks like the warmest upcoming period in Saint Clair County at 86 degrees F.
Tuesday Night is the coolest period ahead with temperatures near 65 degrees F.
The strongest winds are forecast for Tuesday at about 3 to 9 mph E.
Precipitation is mentioned in 5 upcoming forecast periods.
Forecast Details
- Last updated
- May 21, 2026 9:44 PM CDT
- Coverage
- 3 days
- Time zone
- America/Chicago
- Forecast office
- LSX
- Radar station
- KLSX
Weather data is provided by the National Weather Service and refreshed automatically for U.S. locations.
Open NOAA sourceExtended Forecast
Showers and thunderstorms likely. Mostly cloudy, with a low around 65. Chance of precipitation is 60%.
A chance of showers and thunderstorms before 1pm, then a chance of showers and thunderstorms. Partly sunny, with a high near 84. Chance of precipitation is 50%.
A chance of showers and thunderstorms. Partly cloudy, with a low around 66. Chance of precipitation is 50%.
A slight chance of rain showers before 7am, then a chance of showers and thunderstorms. Mostly sunny, with a high near 86. Chance of precipitation is 50%.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Tuesday
May 26
|
Showers And Thunderstorms Likely
|
82°F |
3 to 9 mph
E
|
|
Tuesday Night
May 26
|
Showers And Thunderstorms Likely
|
65°F |
5 to 8 mph
SE
|
|
Wednesday
May 27
|
Chance Showers And Thunderstorms
|
84°F |
5 to 8 mph
SE
|
|
Wednesday Night
May 27
|
Chance Showers And Thunderstorms
|
66°F |
3 to 7 mph
SE
|
|
Thursday
May 28
|
Chance Showers And Thunderstorms
|
86°F |
3 to 7 mph
SE
|
Major City Forecasts
Live forecast snapshots for major cities across Saint Clair County.
Coverage
Forecast coverage currently spans 15 of 15 mapped cities in Saint Clair County.
Largest mapped city population in this region: 40,536.
