Flood Warning Issued for Cook County IL and Northwest Indiana
This alert is no longer in effect.
NOAA issued it on July 31, 2026, 3 weeks 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.
A Flood Warning is in effect until 6:15 AM CDT Monday for Cook County in Illinois and Lake and Porter counties in Indiana due to excessive rainfall.
Read this weather record in 30 seconds
- Record type
- Flood Warning
- Affected area
- Northeast Illinois and Northwest Indiana
- Issued
- July 31, 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 3 weeks ago; use the issuing agency's live warning service for current conditions in Northeast Illinois and Northwest Indiana.
Alert Details
Flood Warning issued by NWS Chicago IL. Effective from June 22, 2026 at 12:29 AM CDT until June 22, 2026 at 6:15 AM CDT. Severity: Severe. Certainty: Likely.
Affected Areas
Cook County, IL; Lake County, IN; Porter County, IN. Specific locations include Chicago, Hammond, Gary, Tinley Park, Calumet City, Portage, Merrillville, Valparaiso, Chicago Heights, Roseland, East Chicago, Schererville, Hobart, Lansing, Oak Forest, Harvey, Highland, Blue Island, Munster and Dolton.
What You Should Do
A Flood Warning means flooding is imminent or may already be occurring. Persons along rivers, creeks, and other waterways should take immediate precautions to protect life and property. Be especially cautious at night when it is harder to recognize the dangers of flooding.
Expected Conditions
Flooding caused by excessive rainfall is expected. Between 2 and 2.5 inches of rain have fallen. Creeks and streams may rise out of their banks. Flooding may occur in poor drainage and urban areas. Underpasses may be flooded. Flooding is ongoing along portions of the Little Calumet, Thorn Creek, Butterfield Creek and Hart Ditch.
Timeline
The warning is effective until 6:15 AM CDT. The heavy rainfall is expected to end overnight, but area streams and rivers will remain elevated through the night.
Original source: NOAA Official Notice ↗
Related Weather Alerts
All Weather Alerts →Nationwide notices with similar length or severity timing 8
Two Areazine-derived peer sets for this NWS weather alert: nearest notices by body length and by same severity near the same agency date. Peers come from other categories so they are not the same-feed Related list above.
Similar body length
Nearest notices by article body length (1,320 characters here).
Similar severity timing
Same severity (high) notices issued closest in time to July 31, 2026.
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