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Flash Flood — Winnebago, IL

Aug 18, 2025

During the afternoon and evening of the 18th, a few rounds of thunderstorms brought torrential rainfall to much of northern Illinois resulting in flash flooding. One particularly strong storm also produced damaging winds in DeKalb County. Initial reports estimate $8.8 million in flood damages around northern and northeast Illinois, and around $2.5 million in the city of Chicago alone.

Source: NOAA National Weather Service Storm Events Database (event 1288629). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Winnebago, IL

This event is one of many recorded floods in Winnebago County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.

View Winnebago County flood data →

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