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Flash Flood — Polk, IA

Jun 30, 2014

A very dynamic pattern was in place over the state with a closed low located over southern Canada into the north central U.S. A very strong jet of 85 to 100 kts as present at 250 mb. CAPE by early morning was already 3000 to 4000 J/kg with downdraft CAPE of 1000 to 1400 J/kg. CAPE in the -10 to -30 C layer of the atmosphere was between 1000 and 1400 J/kg. The freezing level was around 14,000 feet with precipitable water values near 2 inches. The LCL remained around 750 meters with 75 J/kg o

Source: NOAA National Weather Service Storm Events Database (event 516320). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Polk, IA

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

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