Jul 12, 2018
Thunderstorms developed along an outflow boundary very late in the afternoon near the Nebraska border. These storms were slow moving with weak flow aloft and anchored on this nearly stationary boundary through the evening hours. Precipitable water approached 2 inches with up to 3500 J/kg MLCAPE south of the boundary. A band of rainfall from 3 to 5 inches occurred during the evening hours from near Gregory to Parkston.
Source: NOAA National Weather Service Storm Events Database (event 773187). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Gregory County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.