Flash Flood Warning for Boone and Winnebago Counties in Illinois
This alert is no longer in effect.
NOAA issued it on April 15, 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.
A Flash Flood Warning has been issued for Boone and Winnebago counties in north central Illinois, with heavy rain expected to cause rapid flooding until early Wednesday morning.
Read this weather record in 30 seconds
- Record type
- Flash Flood Warning
- Affected area
- Northern Illinois
- Issued
- April 15, 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 Northern Illinois.
Alert Details
The National Weather Service in Chicago has issued a Flash Flood Warning for the affected areas. This alert is effective from 8:37 PM CDT on April 14, 2026, until 2:45 AM CDT on April 15, 2026.
Affected Areas
The warning covers Boone County and Winnebago County in north central Illinois. Specific locations include Rockford, Belvidere, Loves Park, Machesney Park, Roscoe, South Beloit, Rockton, Poplar Grove, Rockford Airport, Candlewick Lake, Cherry Valley, Winnebago, Davis Junction, Pecatonica, Lake Summerset, Durand, Capron, Timberlane, New Milford, and Garden Prairie.
What You Should Do
Persons along creeks, drainage ditches, and other waterways should take immediate precautions to protect life and property. Turn around, don't drown when encountering flooded roads, as most flood deaths occur in vehicles.
Expected Conditions
Doppler radar indicates a line of thunderstorms producing heavy rain with rates of 1 to 2.5 inches per hour. Additional rainfall amounts of 0.5 to 2.5 inches are possible in the warned area, leading to flash flooding of creeks, streams, drainage ditches, streets, underpasses, low-lying areas, and other poor drainage areas.
Timeline
The alert is effective from 8:37 PM CDT on April 14, 2026, and will expire at 2:45 AM CDT on April 15, 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 (1,312 characters here).
Similar severity timing
Same severity (high) notices issued closest in time to April 15, 2026.
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