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Flash Flood — Union, IL

May 26, 2016

A southerly wind flow of very moist and unstable air fed a slow-moving thunderstorm complex. To the south of the complex, surface dew points were in the lower 70's and instability was quite high. An outflow boundary moved southward ahead of the storms, providing the lift necessary for new storms to develop. The result was locally very heavy rainfall as storms repeatedly moved over the same areas. Isolated storms produced large hail.

Source: NOAA National Weather Service Storm Events Database (event 630175). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Union, IL

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

View Union County flood data →

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