Sep 21, 2011
A deep upper trough that extended from the upper Great Lakes to the Gulf of Mexico resulted in deep southwesterly flow across the region, allowing copious amounts of Gulf and Atlantic moisture to stream into the area. A disturbance in the southwesterly flow aloft triggered storms to develop over central North Carolina. Training of slow moving thunderstorms, with rainfall rates in excess of 2 inches per hour, caused flash flooding in Raleigh.
Source: NOAA National Weather Service Storm Events Database (event 347398). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Wake County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.