Jun 8, 1999
A strong upper level disturbance moved north-northeast into Iowa during the afternoon hours. A very unstable airmass was in place over the state with lifted indices near -10 degrees C. Surface dew points were in the low 70s as high temperatures soared into the upper 80s and 90s. This combined to produce CAPE values near 5000 J/kg. Thunderstorms erupted initially developed in more or less an east to west line. That line lifted north and as it did produced very heavy rain and some hail of
Source: NOAA National Weather Service Storm Events Database (event 5698928). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Black Hawk County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.