Oct 11, 2012
A strong upper-level low pressure system dug south along the West Coast, moving inland directly over southern California. A vorticity maximum rotating around the low, along with the setup of a California Bight Coastal Convergence Zone (between drainage winds off the land and onshore flow from the low) created the perfect conditions for showers, thunderstorms and funnel clouds. The cold air instability and warm waters resulted in waterspouts and ocean-effect instability showers over the coastal w
Source: NOAA National Weather Service Storm Events Database (event 415341). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Riverside County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.