Aug 4, 2004
A very unstable airmass was over Iowa during the afternoon of the 3rd. A cold front sank into northern Iowa during the afternoon. Numerous outflow boundaries were located over the state from previous convection as well. Temperatures rose into the mid 80s to low 90s, while dew point readings soared into the upper 70s to low 80s. By late afternoon, lifted indices were around -15 C., with CAPE values in the 6000 to 8000 J/kg range. During the day, a strong MCS tracked east across southern Minn
Source: NOAA National Weather Service Storm Events Database (event 5415491). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Decatur County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.