Flash Flood Warning Issued for McHenry County, IL
This alert is no longer in effect.
NOAA issued it on July 7, 2026, 6 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 McHenry County in northeastern Illinois until 10:00 PM CDT on June 11, 2026, due to heavy rainfall from thunderstorms.
Read this weather record in 30 seconds
- Record type
- Flash Flood Warning
- Affected area
- McHenry County, Illinois
- Issued
- July 7, 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 6 weeks ago; use the issuing agency's live warning service for current conditions in McHenry County, Illinois.
Alert Details
A Flash Flood Warning has been issued by NWS Chicago IL. The alert is effective from June 11, 2026 at 6:27 PM CDT until June 11, 2026 at 10:00 PM CDT.
Affected Areas
The warning covers McHenry County in northeastern Illinois. Some locations that will experience flash flooding include Crystal Lake, Algonquin, Lake in the Hills, McHenry, Woodstock, Huntley, Fox Lake, Harvard, Island Lake, Marengo, Cary, Johnsburg, Lakemoor, Spring Grove, Fox River Grove, Barrington Hills, Wonder Lake, Lakewood, Pistakee Highlands and Oakwood Hills.
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 6:27 PM CDT, Doppler radar indicated thunderstorms producing heavy rain across the warned area. Up to 1 inch of rain has fallen. The expected rainfall rate is 1 to 2 inches in 1 hour. Additional rainfall amounts of 1 to 2 inches are possible in the warned area. Flash flooding is ongoing or expected to begin shortly.
Timeline
The alert is in effect from June 11, 2026 at 6:27 PM CDT until June 11, 2026 at 10:00 PM CDT.
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 (1,245 characters here).
Similar severity timing
Same severity (high) notices issued closest in time to July 7, 2026.
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