March 07--A cold storm system moving through southwest California pelted commuters with rain, thunder and lightning Monday, as National Weather Service forecasters warned of moderate to heavy rainfall and strong winds throughout the day.
Heavy downpours, lightning and hail were reported throughout the morning, briefly knocking out power to Los Angeles International Airport and prompting forecasters to issue severe thunderstorm warnings throughout Los Angeles, Orange and San Diego counties, as well as the Inland Empire.
"This storm is moderately intense," said Alex Tardy, a meteorologist with the National Weather Service in San Diego. "It's not normal for the past five years, considering what's going on with the drought, but we should be getting storms like this in the middle part of the winter. It's not spectacular, but it's a healthy storm."
At least two lightning-related tree fires were reported Monday morning in Los Angeles, said Brian Humphrey, spokesman for the Los Angeles Fire Department. The fires did not spread to any homes or structures, he said.
LIVE BLOG: Thunder and lightning! Severe weather hits Southern California
The storm system brought nearly a half inch of rain to downtown Los Angeles from 10 p.m. Sunday to 10 a.m. Monday, according to the National Oceanic and Atmospheric Administration.
In the same time period, Malibu received 0.38 inch of rain, Long Beach received 0.13 inch, Santa Barbara 0.45 inch and Escondido 0.46 inch.
The steadiest rain was expected to be early in the day as the cold front moved through the region. Behind the cold front, rainfall will become "more showery," with thunderstorms possible throughout the afternoon and evening, the weather service said.
Thunderstorms will be capable of producing debris flow near burn areas. Forecasters issued a flash flood warning early Monday for the Solimar burn area in western Ventura County.
North winds will be the strongest through the Interstate 5 corridor into the San Fernando Valley and over the Santa Monica Mountains, according to the weather service.
The storm brought pea-sized hail to much of the Southland, covering the ground in areas near Sierra Madre and Altadena, said Stuart Seto, a weather specialist with the National Weather Service in Oxnard. In areas experiencing thunderstorms, lightning is possible throughout the evening, he said.
The system also brought strong winds, with reports of gusts up to 64 mph near Point Mugu in the Santa Monica Mountains and gusts over 50 mph in other mountain areas, Seto said.
In San Diego County, Solana Beach reported gusts of 57 mph, and Imperial Beach gusts of 48 mph, Tardy said.
Forecasters issued a winter storm warning for mountains in Los Angeles and Ventura counties and have warned against mountain travel, saying significant snow accumulation is expected above 6,000 feet, with light snow accumulation possible down to 4,000 feet, low enough to affect drivers traveling through the Grapevine.
Many areas above 5,000 feet will see five to 10 inches of snow by Monday night, forecasters said.
A winter storm warning will remain in effect through 4 a.m. Tuesday in the Los Angeles County and Ventura County mountains, Seto said.
"Travel in the mountains should be avoided, but if it is necessary, carry chains and a survival kit," the weather service said in a statement.
Tuesday is expected to be cloudy and the start of a gradual warmup as the cold front moves out, Seto said. Still, temperatures are expected to be chilly this week.
In downtown Los Angeles, the predicted high temperature for Monday is 62 degrees, several degrees below normal, he said. High temperatures are forecast in the low 70s through the week downtown and are expected to drop Saturday "as we get another shot of showers coming at us," Seto said.
Monday's stormy weather follows a period of heavy rain Saturday night and Sunday morning -- rainfall that led to a doubling of traffic accidents and the rescue of several people and a dog along the Los Angeles River, according to KTLA-TV.
Some flights were delayed at Los Angeles International Airport when lightning strikes briefly knocked out power in all terminals, the Associated Press reported. LAX spokeswoman Nancy Castles said backup systems kicked in after electricity was lost around 6 a.m.
Castles said heavy lightning was spotted as the storm cell passed over the airport west of downtown Los Angeles. Power was restored in all terminals within about an hour. Castles said two flights were diverted to LA-Ontario International Airport. Some arriving and departing flights were delayed, but no cancellations were reported.
Though lightning and thunder are rare events in Southern California, they are not unheard of. In July of last year, a summer storm left thousands without power amid hundreds of lightning strikes and heavy downpours. In July 2014 a thunderstorm struck Venice Beach and killed one person.
In Northern California, a winter storm that brought several feet of snow over the weekend continued to cause havoc Monday morning, prompting some school closures and delays for mountain communities along the Sierra Nevada.
Snow and treacherous road conditions forced the Pollock Pines Elementary School District in El Dorado County to close two schools, and other districts delayed classes.
The Lake Tahoe area received three to five feet of new snow over the weekend, said National Weather Service meteorologist Zach Tolby. The California Highway Patrol shut down the Donner Pass at Interstate 80 for a time Sunday because of blizzard conditions.
hailey.branson@latimes.com
veronica.rocha@latimes.com
Follow us on Twitter at @haileybranson / @VeronicaRochaLA
