Jun 1, 2011
A record rain event in May in eastern Montana combined with high water from other storms in April and May and brought high water to the Missouri River chain of reservoirs. Water levels were further increased by the melting of a above normal snow pack in the northern Rockies. The high water levels, plus the threat of flood waters due to the unusually high snow pack in the Rockies and additional heavy rains over the upper Missouri River Basin all contributed to record releases from the Missouri
Source: NOAA National Weather Service Storm Events Database (event 297291). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Harrison County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.