Cold, fast-moving storm could bring rain to Southern California, snow to mountains and even Antelope Valley

LOS ANGELES — Snow is expected today and Saturday in the San Gabriel Mountains in Los Angeles, Ventura and Santa Barbara counties, and a dusting of snow is possible in the Antelope Valley, thanks to a cold and fast-moving storm system, forecasters said.

In urban areas, forecasters said there’s a 20 percent chance of showers in L.A. County today and a “slight chance” of the same in Orange County.

The chance of rain rises to 60 percent in portions of San Bernardino and Riverside counties.

A winter weather advisory warning issued by the National Weather Service to warn of difficult travel conditions will be in effect in the San Gabriel Mountains from 10 this morning until 4 Saturday afternoon.

Behind the system’s front, the snow level is expected to lower to between 3,500 and 4,500 feet, although it will fall to 2,500 feet in Ventura County, according to an NWS statement.

The highest snow amounts will be in Ventura County and in Los Angeles County in the vicinity of The Grapevine along Interstate 5, where “even small accumulations … can cause delays or even road closures,” it said. Three to 6 inches of snow are expected in Ventura County, 2 to 4 inches in Santa Barbara County and 3 inches or less in Los Angeles County on Interstate 5 over the Grapevine.

“And a dusting of snow could occur across the Antelope Valley foothills Friday evening,” the statement warned.

The snow level will be around 7,500 feet early this morning, “then plummet to between 3,500 and 4,000 feet by this afternoon, then down to 2,500 feet across the northern slopes through early Saturday morning,” according to the statement.

At the same time, strong winds will buffet the mountains. Northwest winds of 15 to 25 miles per hour gusting to 40 mph are expected in the mountains early this afternoon, increasing to between 20 and 30 mph with 50-mph gusts by tonight, persisting through early Saturday morning, the NWS said.

Storm activity can be seen in many Western states on Friday, Jan. 19, 2018, including Northern California, and the Pacific Northwest. There is a chance of rain in Southern California, with possible snow in local mountains and even in the Antelope Valley as a cold storm moves swiftly through the area. (Enhanced infrared satellite map courtesy of the National Weather Service)

“Periods of snow, gusty winds, and low visibilities make for dangerous driving conditions and could lead to road closures and travel delays,” warned the NWS statement. It said roadways likely to be affected will include Interstate 5 near The Grapevine, Los Angeles Crest Highway, Highway 33 in the mountains in Ventura County and possibly Highway 14, including the city of Acton.

In light of expected conditions, the NWS warned motorists to “be prepared for snow covered roads and limited visibilities, and use caution while driving.” Also, “keep an emergency kit in your vehicle which includes a flashlight, food and water, extra clothes and blankets, and tire chains.”

Along the coast, a high surf advisory will be in force until 9 p.m. Saturday in L.A. County and 8 p.m. Saturday in Orange County.

The NWS forecast mostly cloudy weather with a 20 percent chance of rain in Los Angeles County today, along with highs of 53 on Mount Wilson; 57 in Lancaster; 58 in Palmdale; 59 in Avalon; 60 in Santa Clarita; 62 in Northridge; 63 at LAX and in Van Nuys and Woodland Hills; 64 in San Pedro, Torrance, Pasadena, North Hollywood and Burbank; 65 in Downtown L.A. and San Gabriel; and 66 in Whittier, West Covina and Long Beach. Saturday’s temperatures in L.A. County will be roughly the same or slightly lower — up to 4 degrees in some communities — then rise by a few degrees on Tuesday, hitting highs of 70 and 71.

Mostly cloudy skies were also forecast in Orange County, along with highs of 60 in San Clemente; 61 in Laguna Beach, Mission Viejo and Yorba Linda; 62 in Newport Beach; and 63 in Fullerton, Santa Ana, Anaheim and Irvine. Temperatures will be the same or marginally lower Saturday and remain mostly in the 60s for several days.

In San Bernardino County, where there is a 20 percent chance of rain today and a 60 percent chance of rain tonight in most areas, with snow likely in higher elevations, it will be 45 in Big Bear and Running Springs; 57 in Hesperia; 59 in Victorville; 60 in Yucaipa and Rancho Cucamonga; 61 in Ontario; 63 in Redlands and San Bernardino.

In Riverside County, there will be a 20 percent chance of rain today, increasing toward the afternoon with a 60 percent chance tonight and a high of 64 in Riverside; sunny skies today with a 30 percent chance of rain tonight and highs of 70 in Desert Hot Springs, 72 in Palm Springs and 73 in Palm Desert; a 50 percent chance of rain tonight and a high of 60 in Temecula; sunny skies today, mostly cloudy at night with a high of 74 in Indio; sunny today and cloudy tonight with a high of 75 in Blythe; a 60 percent chance of rain this afternoon and tonight with a high of 63 in Hemet, Menifee and Murietta, and 64 in Lake Elsinore and Perris.

The storm is hitting much harder in Northern California and the Pacific Northwest, where enormous waves are being detected in the Pacific Ocean and are being predicted for the coast.