Flood Warning Issued for Thorn Creek in Cook County Through Monday Afternoon
This alert is no longer in effect.
NOAA issued it on April 6, 2026, 4 months ago. Warnings of this kind stay in effect for hours to a few days, so this page is a historical record of what was issued, not a current warning. For conditions where you are right now, check weather.gov (US), weather.gc.ca (Canada), the Met Office (UK), or the Bureau of Meteorology (Australia).
Areazine synthesizes this NWS weather alert directly from NOAA's official public data feed. See our methodology for full source attribution and refresh cadence.
The National Weather Service has issued a Flood Warning for Thorn Creek in Cook County, Illinois, as water levels are expected to crest above the 9-foot flood stage Monday morning.
Read this weather record in 30 seconds
- Record type
- Flood Warning
- Affected area
- Cook County, Illinois
- Issued
- April 6, 2026
- Issuing authority
- NWS Chicago IL
Flood notices turn on location and timing. Treat the named area as this record's scope; do not assume nearby counties, parishes, or waterways were included.
Record status: historical. It was issued 4 months ago; use the issuing agency's live warning service for current conditions in Cook County, Illinois.
Alert Details
The National Weather Service in Chicago IL has issued a Flood Warning for Thorn Creek at Thornton. This alert indicates that minor flood stage is forecasted and water levels above flood stage are imminent.
Affected Areas
The warning specifically affects Cook County, Illinois. The geographic scope includes Thorn Creek from near Glenwood downstream to the confluence with the Little Calumet River, including the Thornton gauge.
What You Should Do
Residents and individuals near rivers and streams in the warned area should take immediate precautions to protect life and property. A Flood Warning means water levels above flood stage are imminent or may already be occurring. The NWS advises the public to avoid flooded areas and monitor local weather updates. The next official statement is expected by 10:00 AM CDT.
Expected Conditions
Minor flooding is anticipated as the river stage continues to rise. As of 4:30 AM CDT Monday, the water level was recorded at 8.9 feet. The flood stage for this location is 9.0 feet. When the river reaches 9.0 feet, water begins to be diverted through the Thorn Creek Diversion Tunnel. The river is expected to crest just over 9 feet later this morning before receding.
Timeline
The Flood Warning is effective as of 4:40 AM CDT on Monday, March 16, and is currently set to expire at 1:00 PM CDT on Monday afternoon. The river is expected to fall below flood stage by early afternoon.
Original source: NOAA Official Notice ↗
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