Weather World
St. Clair County, IL Official WebsiteSt Clair County, IL Weather Forecast
Quick Weather Clicks
Settings
Sun & Moon
St Clair County Weather Forecast
| THIS AFTERNOON | TONIGHT | SATURDAY | SATURDAY NIGHT | SUNDAY | SUNDAY NIGHT | MONDAY | TUESDAY | WEDNESDAY | WEDNESDAY NIGHT | THURSDAY |
 |  |  | | | | | | |  |  |
| Partly Sunny | Mostly Clear | Sunny | Mostly Clear | Sunny | Clear | Clear | Clear | Sunny | Partly Cloudy | Chance of Rain |
| Hi: 45°FHi: 7°C | Lo: 25°FLo: -4°C | Hi: 50°FHi: 10°C | Lo: 25°FLo: -4°C | Hi: 55°FHi: 13°C | Hi: 59°FHi: 15°C Lo: 31°FLo: -1°C | Hi: 59°FHi: 15°C Lo: 31°FLo: -1°C | Hi: 59°FHi: 15°C Lo: 31°FLo: -1°C | Hi: 61°FHi: 16°C | Lo: 41°FLo: 5°C | Hi: 65°FHi: 18°C |
| POP: 20% |
POP = Probability of Precipitation.
Weather Outlook Updated: 1227 PM CST Fri Nov 13 2026 
St Clair County Radar Loop
Use the map search tool if you want to place a location marker on the radar map...
St Clair County Weather Map
St Clair County Quick Facts
St Clair County Forecast Discussion
Meteorlogic Glosserator
Instant definitions for any meteorological term.
Instant definitions for any meteorological term.
Issued: 224 PM CST Fri Nov 13 2026
Key Messages
- A winter-like chill continues through the weekend, bringing a hard freeze for much of the area each night. Temperatures warm back to seasonal normals early next week.
Aviation
/18Z TAFS THROUGH 00Z SUNDAY/... Issued at 1116 AM CST Fri Nov 13 2026
A field of low-VFR stratus (3-5kft) is positioned across eastern MO and IL as of late this morning. This cloud field is expected to remain VFR before slowly advecting and scattering out from north to south later this afternoon. Later tonight a ...