St. Clair County weather alerts
There are no active weather alerts for St. Clair County, IL right now.
Since 2016 the National Weather Service has issued about 918 alerts that included St. Clair County, roughly 92 a year. The most common is the severe thunderstorm warning (223 from 2016 to 2025). The last tornado warning was issued on June 21, 2026. 59 tornadoes have touched down in the county since 1950.
Updated from the National Weather Service · lists refresh hourly; the live map loads current alerts directly from the NWS
No warnings, watches or advisories include St. Clair County at the moment. This page updates automatically when the National Weather Service issues one. Check neighboring St. Louis city, Madison County, Monroe County, St. Louis County.
St. Clair County alert history
Alert events that included St. Clair County or its forecast zones, from the NWS warning archive.
| Alert type | 2016–2025 | 2026 | Last issued |
|---|---|---|---|
| Severe Thunderstorm Warning | 223 | 13 | August 17, 2026 |
| Dense Fog Advisory | 74 | 4 | May 9, 2026 |
| Severe Thunderstorm Watch | 73 | 6 | July 10, 2026 |
| Flood Advisory | 65 | 8 | September 16, 2026 |
| Winter Weather Advisory | 60 | 0 | December 1, 2025 |
| Flood Watch | 48 | 6 | August 6, 2026 |
| Flash Flood Warning | 46 | 4 | July 11, 2026 |
| Wind Advisory | 46 | 3 | June 17, 2026 |
| Heat Advisory | 43 | 6 | September 15, 2026 |
| Flood Warning | 42 | 1 | April 30, 2026 |
| Tornado Watch | 38 | 6 | June 21, 2026 |
| Tornado Warning | 33 | 8 | June 21, 2026 |
| Freeze Warning | 25 | 2 | November 7, 2026 |
| Frost Advisory | 20 | 1 | October 18, 2026 |
| Extreme Heat Warning | 14 | 4 | September 3, 2026 |
| Red Flag Warning | 11 | 1 | March 29, 2026 |
| Winter Storm Warning | 11 | 1 | January 24, 2026 |
| Winter Storm Watch | 11 | 1 | January 24, 2026 |
| Cold Weather Advisory | 10 | 3 | January 27, 2026 |
| Freeze Watch | 7 | 0 | November 2, 2025 |
| Extreme Heat Watch | 6 | 4 | August 31, 2026 |
| High Wind Warning | 3 | 0 | March 5, 2025 |
| Extreme Cold Warning | 3 | 1 | January 26, 2026 |
| Extreme Cold Watch | 2 | 0 | December 22, 2022 |
| Fire Weather Watch | 2 | 0 | October 17, 2020 |
| Ice Storm Warning | 1 | 0 | January 13, 2017 |
| High Wind Watch | 1 | 0 | March 14, 2019 |
Tornado history in St. Clair County
59 tornadoes have been recorded in St. Clair County since 1950, killing 6 people and injuring 106. That ranks 12 of 102 counties in Illinois. The most recent was on April 20, 2025 (rated EF0).
Strongest tornadoes in St. Clair County
| Date | Rating | County | Path length | Width | Deaths | Injuries |
|---|---|---|---|---|---|---|
| May 15, 1968 | F3 | St. Clair County | 2 mi | 200 yd | 4 | 60 |
| April 5, 1958 | F3 | St. Clair County | 60.5 mi | 100 yd | 1 | 8 |
| November 15, 1988 | F3 | St. Clair County | 9 mi | 200 yd | 0 | 0 |
| April 2, 2006 | F2 | St. Clair County | 7 mi | 100 yd | 1 | 11 |
| March 20, 1976 | F2 | St. Clair County | 39 mi | 250 yd | 0 | 0 |
Most recent tornadoes
| Date | Rating | County | Path length | Width | Deaths | Injuries |
|---|---|---|---|---|---|---|
| April 20, 2025 | EF0 | St. Clair County | 0.8 mi | 100 yd | 0 | 0 |
| April 19, 2025 | EF0 | St. Clair County | 0.5 mi | 25 yd | 0 | 0 |
| March 14, 2025 | EF2 | St. Clair County | 11 mi | 700 yd | 0 | 0 |
| March 14, 2025 | EF1 | St. Clair County | 6.8 mi | 450 yd | 0 | 0 |
| March 14, 2025 | EF1 | Monroe County | 14.7 mi | 275 yd | 0 | 0 |
About St. Clair County
- Population: 251,149 (2024 estimate)
- State: Illinois
- NOAA Weather Radio SAME code: 017163 (how to use it)