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Flash Flood — Union, IA

May 25, 2010

A warm and humid airmass was in place across Iowa on the 25th. The flow was quite weak with only 5 to 10 kts of shear. Afternoon temperatures warmed into the 80s with dew points in the mid 60s to around 70. There was a fair amount of instability with available CAPE around 3500 J/kg by early to mid afternoon. A weak cold frontal boundary extended from north central into southwest Iowa by mid afternoon. Thunderstorms developed in the unstable air ahead of this boundary. Spotty reports of hig

Source: NOAA National Weather Service Storm Events Database (event 221728). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Union, IA

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.

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