Aug 20, 2007
As the storms that produced the flash flooding during the previous night moved off, an MCS that moved across South Dakota during the night moved into northwest Iowa. The storms intensified as they moved into a richer moisture environment across northwest Iowa with precipitable water values in the 1.75 to 2 inch range. There was plenty of instability in the atmosphere with CAPE values in the elevated layer between 2000 and 4000 J/kg. The environment exhibited a strong shear with effective shea
Source: NOAA National Weather Service Storm Events Database (event 41710). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Humboldt County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.