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Flash Flood — Union, IA

Jun 25, 2011

A strong push of moisture took place during the overnight hours of the 24th into the morning of the 25th. The low level jet increased to 60 kts, bringing a return of moisture to the area. Precipitable water values increased to just under 2 inches by morning. An MCS developed the previous night over South Dakota and Nebraska. It pushed east during the night and consolidated over Nebraska. The airmass was unstable to the south of the developing MCS, with CAPE values around 2000 J/kg and lift

Source: NOAA National Weather Service Storm Events Database (event 303535). 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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