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Flash Flood — Polk, IA

Jun 30, 2018

A frontal boundary was draped across areas just west of Iowa during the morning hours of June 30th, and slowly moved eastward into the state throughout the day. By the afternoon, it had made its way into central portions of the state, draping itself in a southwest to northeast fashion. Ahead of the front, the convective environment was ripe, with MUCAPE values in excess of 4000 J/kg and effective shear in the 30 to 40 kt range, with best values near the front. While there was reason for concern

Source: NOAA National Weather Service Storm Events Database (event 764987). 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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