Mar 10, 2023
A large upper trough off the Pacific Northwest coast pulled up a deep moisture fetch from the Pacific Ocean which spread inland into central California on March 9 and 10. This atmospheric river event produced 4 to 8 inches of liquid precipitation across much of the Sierra Nevada. With this moisture being of tropical origin, snow levels were high and were above 9500 feet for much of this event. The rain falling on top of a large snowpack over the Sierra Nevada produced a large amount of runoff re
Source: NOAA National Weather Service Storm Events Database (event 1076279). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Mariposa County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.