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Flash Flood — Cass, IA

May 16, 1999

As was mentioned above, the weather pattern was very active over the central U.S. A cold front had become stationary to the west of Iowa during the afternoon of the 16th. This set the stage for a serious weather situation. During the afternoon, 70 degree F. surface dew point temperatures were widespread for the first time of the season. The airmass became very unstable as the upper levels were still relatively cool. CAPE values during the few hours just prior to the development of the thund

Source: NOAA National Weather Service Storm Events Database (event 5693504). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Cass, IA

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

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More Flood Stories

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