May 11, 2011
A very warm and humid airmass was in place over Iowa on the 11th. During the previous two days, strong capping was in place across the state. A cold front began to move into the state on the 11th as upper level heights and temperatures began to fall. The front stalled however, and the atmosphere became unstable due to the cooling aloft. The freezing level was relatively low on the 11th as it fell to under 12,000 feet. Most unstable CAPE was in the 1500 to 2500 J/kg range by the afternoon as
Source: NOAA National Weather Service Storm Events Database (event 290651). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Adams County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.