Illinois Flood Warning | Effective 04/20/2026 09:36

Headline: 
Flood Warning issued April 20 at 11:36AM CDT until April 23 at 1:00PM CDT by NWS Chicago IL
Event: 
Flood Warning
Urgency: 
Immediate
Effective: 
April 20, 2026 - 9:36am
Expires: 
April 21, 2026 - 3:45am
Description: 
...The Flood Warning is extended for the following rivers in Illinois... Kishwaukee River near Perryville affecting Winnebago County. ...The Flood Warning continues for the following rivers in Illinois... Rock River at Byron affecting Ogle County. Illinois River at La Salle affecting La Salle, Bureau and Putnam Counties. Pecatonica River near Shirland affecting Winnebago County. Rock River at Rockton affecting Winnebago County. Rock River at Latham Park affecting Winnebago County. Fox River at Montgomery affecting Kendall and Kane Counties. Des Plaines River at Lincolnshire affecting Cook and Lake IL Counties. Des Plaines River near Russell affecting Lake IL County. Des Plaines River near Gurnee affecting Lake IL County. ...Observed flooding changed to Minor severity for the following rivers in Illinois... Rock River at Dixon affecting Lee and Ogle Counties. * WHAT...Moderate flooding is occurring and moderate flooding is forecast. * WHERE...Rock River from Confluence with Kishwaukee River to Castle Rock State Park near Oregon, including the Byron gauge. * WHEN...Until early Thursday afternoon. * IMPACTS...At 15.5 feet, Water threatens lower sections of the water treatment plant property in Byron. Water threatens IL-2 west of Byron. * ADDITIONAL DETAILS... - At 10:15 AM CDT Monday the stage was 14.8 feet. - Recent Activity...The river stage began falling overnight. - Forecast...The river is expected to slowly fall the next several days. - Flood stage is 13.0 feet. - http://www.weather.gov/safety/flood
Instruction: 
A Flood Warning means water levels above flood stage are imminent or may already be occurring. Persons along rivers and streams in the warned area should take immediate precautions to protect life and property. These forecasts are based on observed precipitation as well as forecast precipitation 24 hours into the future. Changes to the rainfall forecast, or any additional rainfall after 24 hours, may cause changes to these river forecasts. Additional information is available at www.weather.gov. The next statement will be issued by this evening.
Area Description: 
Ogle, IL
Forcast Office: 
NWS Chicago IL
Sender: 
w-nws.webmaster@noaa.gov