Jul 8, 2019
A surface boundary stretching from southwest into north central North Dakota served as the primary focal point for thunderstorm development in an atmosphere of very high instability. Initially, large hail was the main threat, though a couple of tornadoes developed in an area of enhanced low level shear. Later, storms mainly developed along an old outflow boundary and were slow moving. This combined with a moisture rich atmosphere which led to a heavy rain threat, in addition to a hail and strong
Source: NOAA National Weather Service Storm Events Database (event 831940). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Sioux County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.