Updated Sunday, March 1 – 2:56 pm
A winter storm arrived in the Southland with a bang today, as the National Weather Service said it’s tracking a strong thunderstorm near Santa Monica.
The slow-moving storm likely will bring local flooding across portions of West Los Angeles and the San Fernando Valley from Woodland Hills to areas including Van Nuys and North Hollywood, NWS officials said in a special weather statement at 2:33 p.m.
Heavy rain, hail up to one-half inch and lightning also were possible in those regions, according to the weather service
Rain also was falling in Marina Del Rey and surrounding coastal communities, as it was in portions of Orange County, including Anaheim, where Disneyland patrons and employees were forced to use umbrellas and don rain gear.
The storm — fueled by a cold low-pressure system — began its sweep into Southern California Saturday, bringing blustery winds from coastal regions to inland mountains ranges.
“A moist and unstable air mass in place from a cold upper low pressure system will bring showers and a slight chance of thunderstorms to the area through Monday,” the NWS said in a statement released at 2:09 p.m. “A weaker storm system will follow on its heels later Monday, allowing for lingering showers into early Tuesday.”
Dry and warmer weather was expected late Tuesday through Friday, the NWS said.
The weather service said approaching precipitation expected tonight through Monday could cause hazardous conditions on Interstate 5 over the Grapevine, and perhaps in the foothills near the Antelope Valley (14) Freeway.
Showers — and snow above 6,000 feet in elevation — were expected to increase in the mountains, with the snow level dropping to between 3,500 and 4,000 feet today and tonight. Both the 5 and 15 freeways top out just above 4,100 feet.
Thunderstorms, thunder snow and hail storms are possible, NWS officials said.
Snow levels could drop to below 3,500 feet, threatening the 14 Freeway, which crests at 3,258 feet above sea level near Escondido Canyon Road in Acton. Earlier, the NWS predicted an average of eight-to-12 inches of snow above 6,500 feet; two to five inches of snow between 4,000 and 5,000 feet.
Highest mountain peaks, like at Mountain High and Mount Baldy ski areas, could get up to 18 inches of snow.
Two inches of snow would be possible at the lowest snowfall elevations, the NWS said.
Chain requirements were in effect overnight for Highway 243 near Idyllwild, and for the highways to and through the Big Bear and Lake Arrowhead resort areas.