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Flash Flood — Williamson, IL

Aug 13, 2016

A series of thunderstorm complexes over a period of several days resulted in locally significant flash flooding. A cold front stalled across the Lower Ohio and Mid-Mississippi Valleys, where tropical moisture was already in place. Precipitable water values from 2.25 to 2.5 inches were common. A sub-tropical low pressure system that produced torrential rains along the Gulf of Mexico coast then turned north, eventually getting pulled northeast across Missouri along the stalled cold front. This low

Source: NOAA National Weather Service Storm Events Database (event 652375). 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.

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