More than 1,400 lightning strikes jolted Southern California over the weekend during a rare summer thunderstorm in which a 20-year-old man died and several others were injured, officials said.
A map released Tuesday by the National Weather Service shows that in southwestern San Bernardino County alone, there were 858 cloud-to-ground strikes, meaning lightning actually hit water or land sometime between Friday and Monday.
"It's an unusual amount of lightning strikes ... for any time of year for that matter," said James Thomas, a meteorologist for the National Oceanic and Atmospheric Administration.
The weather service recorded 28 lightning strikes in Los Angeles County, some of which struck along Venice Beach, where 13 people were injured. Among them was Nick Fagnano, 20, of Los Angeles, who was pronounced dead not long after he was pulled out of the ocean during the lightning storm.
Bill Patzert, a climatologist with NASA's Jet Propulsion Laboratory, said Sunday's extremely rare weather event occurred when a strong high pressure system pulled an unusual mass of hot, moist air up from Mexico and the Gulf of California to the coastal areas, creating the unstable atmospheric conditions.
The unusual weather pattern brought with it strikes all along the Southern California coast, making for an "impressive" storm, Thomas said.
Seventy-five lightning strikes were logged along San Diego County coastal waters.
An additional 248 strikes were reported in inland San Diego County, while 228 bolts of lightning hit western and central Riverside County.
Lightning could continue Tuesday, with afternoon thunderstorms possible in the San Bernardino, Riverside and San Diego county mountains, according to the National Weather Service.
The afternoon storms could produce heavy rainfall, gusty winds and lightning, forecasters warned.