Flash Flood Warning Issued for Cook and DuPage Counties in Illinois
This alert is no longer in effect.
NOAA issued it on August 1, 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.
NWS Chicago has issued a Flash Flood Warning for central Cook County and southeastern DuPage County until 11:45 AM CDT on August 1.
Read this weather record in 30 seconds
- Record type
- Flash Flood Warning
- Affected area
- Northeastern Illinois
- Issued
- August 1, 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 Northeastern Illinois.
Alert Details
A Flash Flood Warning has been issued by the National Weather Service in Chicago IL. The alert is effective from August 1 at 7:41 AM CDT until August 1 at 11:45 AM CDT.
Affected Areas
The warning covers central Cook County and southeastern DuPage County in northeastern Illinois. Locations that will experience flash flooding include Downers Grove, Elmhurst, Lombard, Addison, Woodridge, Glen Ellyn, Melrose Park, Maywood, Brookfield, Franklin Park, Hinsdale, Westchester, Lemont, La Grange, Burr Ridge, Oak Brook and Elmwood Park.
What You Should Do
A Flash Flood Warning means rapid-onset flooding is imminent or may already be occurring. Persons along creeks, drainage ditches, and other waterways should take immediate precautions to protect life and property.
Expected Conditions
At 7:41 AM CDT, Doppler radar and automated rain gauges indicated thunderstorms producing heavy rain across the warned area. Up to 3 inches of rain have fallen. Additional rainfall amounts of 1 to 2 inches are possible. Flash flooding is ongoing or expected to begin shortly.
Timeline
The alert is in effect from 7:41 AM CDT to 11:45 AM CDT on August 1, 2026.
Original source: NOAA Official Notice ↗
Related Weather Alerts
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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 (1,177 characters here).
Similar severity timing
Same severity (high) notices issued closest in time to August 1, 2026.
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