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Flash Flood — Hamilton, IL

Jun 30, 2020

The combination of very weak flow aloft and an anomalously unstable and moist environment along a residual outflow boundary promoted the development of thunderstorms across the mid Mississippi and lower Ohio Valleys through the late afternoon into mid evening. A weak shortwave slowly advanced eastward along the bootheel of Missouri, while a weak impulse moved southeast from the northern border of Missouri. An outflow boundary was the primary focus for renewed development of thunderstorms in the

Source: NOAA National Weather Service Storm Events Database (event 899098). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Hamilton, IL

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

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