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Flash Flood — Jefferson, IL

Mar 19, 2020

Short lines of thunderstorms with embedded circulations moved across southern Illinois during the afternoon of the 19th. Widespread heavy rain caused isolated flash flooding. The storms occurred just south of a warm front under a very strong southwest low level flow, around 60 knots at 850 mb. An upper level disturbance over the Ozark Mountains contributed to the storms.

Source: NOAA National Weather Service Storm Events Database (event 876271). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Jefferson, IL

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

View Jefferson County flood data →

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