Jul 28, 2008
A very unstable airmass was in place over Iowa as a warm front lifted north slowly into the state. The warm air had moved in aloft as freezing levels increased from 14,600 feet in the morning, to 16,200 by the evening hours. The atmosphere was a high CAPE, moderate to high shear with CAPE rising to near 5000 J/kg by late afternoon. Lifted indices fell to -8 to -13 C. A speed max moved across the state during the late afternoon and evening hours with shear increasing to between 45 and 60 kts.
Source: NOAA National Weather Service Storm Events Database (event 107478). Narrative written by NWS staff at the time of the event.
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.