Illinois flash flood warnings
There are no flash flood warnings in Illinois right now. The last one was issued on September 20, 2026.
Flash flooding is happening or about to happen. Move to higher ground and never drive through flooded roads.
Updated from the National Weather Service · lists refresh hourly; the live map loads current alerts directly from the NWS
Active flash flood warnings in Illinois
None right now. Other active alerts in Illinois: none.
Flash Flood Warnings in Illinois by year
Illinois averaged 114.6 flash flood warnings per year from 2016 to 2025, and has had 218 so far in 2026. The most recent was issued on September 20, 2026.
Counties with the most flash flood warnings
| County | 2016–2025 |
|---|---|
| Cook County | 62 |
| St. Clair County | 46 |
| Madison County | 45 |
| Will County | 44 |
| Sangamon County | 43 |
| Tazewell County | 42 |
| Franklin County | 40 |
| Fayette County | 39 |
| Jackson County | 39 |
| White County | 37 |
What a flash flood warning means
A flash flood warning means water is rising fast, usually within six hours of heavy rain, a dam or levee failure, or an ice jam. Small streams, low-water crossings, urban underpasses and burn scars from wildfires are the most dangerous places. A "flash flood emergency" is the highest level and is used when severe threat to life and catastrophic damage are occurring.
More about flash flood warnings and the national map →
What to do
- Get to higher ground immediately if you are in a flood-prone area.
- Turn around, do not drown: never drive or walk into flood water.
- Stay away from creeks, drainage ditches and low-water crossings.
- At night, be extra careful; it is harder to see that a road is flooded.
More Illinois alerts
- Tornado Warnings
- Tornado Watches
- Severe Thunderstorm Warnings
- Flood Warnings
- Flood Watches
- Winter Storm Warnings
- Winter Storm Watches
- Winter Weather Advisories
- Cold Weather Advisories
- Freeze Warnings
- Frost Advisories
- Heat Advisories
- Extreme Heat Warnings
- High Wind Warnings
- Wind Advisories
- Red Flag Warnings
- Dense Fog Advisories
- All Illinois alerts