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Flash Flood — Williamson, IL

Apr 29, 2017

During the evening, clusters of storms developed just north of a surface warm front that extended from the Missouri bootheel northeastward along the Ohio River. The warm front became stationary, and the area of storms tracked northeast across the same areas through the overnight and early morning hours. The repeated bouts of heavy-rain producing storms lasted 8 to 12 hours, resulting in excessive rainfall.

Source: NOAA National Weather Service Storm Events Database (event 687746). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Williamson, IL

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

View Williamson County flood data →

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