May 10, 2019
A closed upper low brought showers and thunderstorms to Southern California on May 10-11. Coastal areas received 0.10-0.25 inch of rain, valley areas received up to 0.50 inch of rain, and some mountain areas received up to an inch of rain. Thunderstorms were observed across valley and mountain areas. Flash flooding was reported in the Coachella Valley. A rock slide was reported on I-8 near Jacumba. Rocks were approximately the size of basketballs. Penny sized hail was reported in Apple Valley.
Source: NOAA National Weather Service Storm Events Database (event 830646). 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.