Snow shuts I-5 in Grapevine area

Snow-clogged roadways forced the closure of Interstate 5 in the Grapevine area in both directions overnight and this morning, stranding hundreds of drivers and redirecting commuters on alternate routes, officials said.

California Highway Patrol officers are trying to aid about 200 motorists stuck in the snow, said CHP Officer Jason Bettini. The Red Cross is on hand to offer aid to motorists.

The snow is “sticking quite a bit,” Bettini said. “Caltrans couldn’t keep up with the snowplows.”

Officials are urging motorists to take California 58 or 46. It is not known when the I-5 will be clear enough to reopen, as forecasters extended a winter storm warning through tomorrow night.

The winter storm that drenched the Southland Wednesday night, with record-breaking rainfall in Santa Barbara, was still bringing scattered showers this morning, said forecaster Stan Wasowski of the National Weather Service in San Diego.

The storm system “is still up there kind of spinning its wheels off the central California coast,” Wasowski said.

Light rain should continue through late this afternoon, when heavier showers are expected with a slight chance of thunderstorms in Los Angeles and Ventura counties. Nearly an inch of rain fell in downtown Los Angeles on Wednesday.

Between 1 and 2 inches of rain are expected in the coastal areas, and as much as 4 inches of rain could fall in foothills and mountains, said Stuart Seto, a weather specialist with the National Weather Service in Oxnard.

A flash-flood watch remains in place through Friday afternoon for burn areas in Ventura County and Los Angeles coastal regions, and residents could face possible debris flows or mudslides, Wasowski said.

A winter storm warning for mountain areas of Los Angeles, Santa Barbara and Ventura counties will remain in effect through tomorrow night. The snow levels should rise from 3,000 feet this morning to 4,000 feet late tonight, according to the National Weather Service.

In northern Los Angeles County, more than a foot of snow fell overnight in Frazier Park, at 5,000 feet, with more snow reported at higher altitudes.

Some mountain roads have been closed due to accumulation, and the weather service warns of dense fog and wind gusts of up to 40 mph blowing snow and reducing visibility to “near zero at times.” Nearly a foot of snow is expected to fall in the San Bernardino mountains overnight.

“There’s kind of a lull right now,” Wasowski said of the storm traveling from the Central Coast, leaving commuters “something to look forward to this afternoon.”

More rain is expected through Saturday, although the tropical moisture moving in will mean warmer precipitation, forecasters said.

susannah.rosenblatt@latimes.com