Jul 1, 2011
A record rain event in May in eastern Montana, other storms in April and May, and snow melt all combined to bring record high water to the Missouri River chain of reservoirs. The high water levels plus a record 13.8 million acre feet of runoff in June (combined rain and snow melt from an unusually high snow pack in the Rockies) and a record 10 million acre feet runoff in July over the Missouri River Basin above Sioux City all contributed to record releases from the Missouri River Reservoirs. Re
Source: NOAA National Weather Service Storm Events Database (event 309590). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Cass County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.