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Flood — Williamson, IL

Apr 24, 2019

A loosely organized cluster of thunderstorms gradually increased due to surface heating ahead of a weak low pressure center over southern Missouri. These storms occurred in a moderately unstable environment, with around 1500 j/kg of cape. Wind shear was relatively weak, however 30 to 35 knots of mid-level flow atop marginal low-level flow resulted in sufficient shear for a weak, brief tornado. Locally heavy rain under the largest storm cluster caused minor road flooding.

Source: NOAA National Weather Service Storm Events Database (event 814402). 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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