Alert archive / Illinois / River Flood Warnings / 2026
River Flood Warnings in Illinois, September 2026
18 river flood warnings in September 2026. An alert counts here when it covered any part of the state, so the counties below add up to more than the state. The archive of river flood warnings reaches back to 2005.
River Flood Warnings by county
Each county as a circle sized by its count in September 2026. Tap one for its archive.
- River Flood Warnings
- 18
- Busiest day
- September 20, 202612 river flood warnings
Over time
By day
Days in UTC, the clock the archive keeps.
The alerts
Every alert, in the order issued. Times are local, Central Time. Each opens its own page with the text, the map, the radar and the sounding.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 19, 9:05 PM CDT | River Flood Warning | LOT | Cook | 17 hr |
| Sep 19, 10:10 PM CDT | River Flood Warning | LOT | LaSalle | 45 hr |
| Sep 20, 9:14 AM CDT | River Flood Warning | LOT | Lake | 21 days |
| Sep 20, 9:23 AM CDT | River Flood Warning | DVN | Henry, Rock Island, Whiteside | 49 hr |
| Sep 20, 9:23 AM CDT | River Flood Warning | DVN | Henry, Rock Island | 3 days |
| Sep 20, 9:35 AM CDT | River Flood Warning | MKX | Lake | 5 days |
| Sep 20, 11:48 AM CDT | River Flood Warning | LSX | Adams | 7 days |
| Sep 20, 11:48 AM CDT | River Flood Warning | LSX | Calhoun | 21 days |
| Sep 20, 11:48 AM CDT | River Flood Warning | LSX | Pike | 7 days |
| Sep 20, 11:48 AM CDT | River Flood Warning | LSX | Adams | 10 hr |
| Sep 20, 11:48 AM CDT | River Flood Warning | LSX | Pike | 6 days |
| Sep 20, 11:48 AM CDT | River Flood Warning | LSX | Calhoun | 21 days |
| Sep 21, 10:21 AM CDT | River Flood Warning | LOT | Lake | 7 days |
| Sep 21, 11:47 AM CDT | River Flood Warning | DVN | Henderson, Mercer | 47 hr |
| Sep 21, 11:47 AM CDT | River Flood Warning | DVN | Henderson | 5 days |
| Sep 21, 11:47 AM CDT | River Flood Warning | DVN | Hancock, Henderson | 5 days |
| Sep 22, 9:36 PM CDT | River Flood Warning | DVN | Hancock | 47 hr |
| Sep 23, 11:53 AM CDT | River Flood Warning | LSX | Pike | 5 days |
By county
Every county with at least one alert. A county page lists each alert that covered it.
Nearby
Sources
National Weather Service watches, warnings, advisories and statements from the Iowa Environmental Mesonet's VTEC archive, which reconstructs tornado, severe thunderstorm, flash flood and marine warnings back to 1986 from the NWS text archive. Storm Prediction Center watches and mesoscale discussions from SPC's archive through the Mesonet. County centers from the US Census Bureau. Warning verification from the Mesonet's Cow. Rebuilt daily.