Mar 11, 2021
Scattered thunderstorms tracked eastward from Missouri across southern Illinois. A deep upper-level low pressure system sank southeast into the far southwestern U.S., pumping plenty of Pacific moisture northeast into the mid Mississippi River Valley as a cold front settled slowly southeast into the region. There was abundant deep moisture in place for locally heavy rain.
Source: NOAA National Weather Service Storm Events Database (event 942590). Narrative written by NWS staff at the time of the event.
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.