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Flash Flood — Williamson, IL

May 8, 2024

A major outbreak of severe weather occurred on the 8th for the Quad State region. On the synoptic scale, a longwave trough was centered across the Rockies with deep-layer southwesterly flow from the Southern Plains to the Ohio Valley. A 110 kt upper jet extended from northern KS to IA while a 60 kt mid-level jet was positioned across northern MZ into IA. Surface low pressure near the MZ/KS border lifted to St. Louis around 12am CST on the 9th. A warm frontal boundary stretched across the Quad St

Source: NOAA National Weather Service Storm Events Database (event 1184515). 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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