Illinois Flood Warning | Effective 04/18/2026 03:44

Headline: 
Flood Warning issued April 18 at 5:44AM CDT until April 21 at 1:00PM CDT by NWS Chicago IL
Event: 
Flood Warning
Urgency: 
Expected
Effective: 
April 18, 2026 - 3:44am
Expires: 
April 18, 2026 - 9:45pm
Description: 
...The National Weather Service in Chicago IL has issued a Flood Warning for the following rivers in Illinois... Illinois River at Ottawa affecting La Salle County. For the Illinois River (Upper)...including Ottawa...Minor flooding is forecast. * WHAT...Minor flooding is forecast. * WHERE...Illinois River from Heritage Harbor east of Ottawa downstream to Starved Rock Lock and Dam, including the Ottawa gauge. * WHEN...From this afternoon to early Tuesday afternoon. * IMPACTS...At 462.5 feet, Roadway entrance to Allen Park threatened in Ottawa. Allen Park west boat ramp inundated in Ottawa. At 464.0 feet, Backwater causes the Fox River to reach bankfull near St. Elizabeth Medical Center in Ottawa. * ADDITIONAL DETAILS... - At 4:30 AM CDT Saturday the stage was 462.2 feet. - Forecast...The river is expected to rise above flood stage later today. - Flood stage is 463.0 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: 
La Salle, IL
Forcast Office: 
NWS Chicago IL
Sender: 
w-nws.webmaster@noaa.gov