May 21, 2019
A powerful storm system slowly moved from the Four Corners region northeastward through the Plains, leading to a prolonged period of precipitation across western South Dakota May 20-22. This three day period was among the coldest, wettest, and snowiest on record for late May, with several temperature and precipitation records set. Runoff from the rain and melting snow led to flooding of creeks, rivers, low-lying areas, and some roads across western and south central South Dakota.
Source: NOAA National Weather Service Storm Events Database (event 831163). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Pennington County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.