Snow levels dipping and widespread rain is on tap for Southern California this week

Nayer Shahram walks in the rain with a broken umbrella during a December storm in Encino.
Nayer Shahram walks in the rain with a broken umbrella during a December storm in Encino.
(Mel Melcon / Los Angeles Times)

Break out the umbrellas and hang onto those heavy coats because the region’s first significant winter storm of 2020 is expected to unleash rain and snow Thursday.

After what has been a mostly dry January, a chilly winter storm is expected to move into the northern portion of the state Tuesday before making its way down the coast to Los Angeles County by late Thursday morning.

The system, which originated just south of Alaska, is expected to dampen the coasts and valleys with up to three-quarters of an inch of rain. The foothills and coastal mountain slopes are on tap to get a bit more precipitation: one-half to 1½ inches, said Lisa Phillips, a meteorologist with the National Weather Service.

“It looks like there’s some good moisture with this system, so we’ll be getting some good rainfall amounts,” she said. “Definitely more than just a sprinkle.”


The storm is also expected to drop snow levels to 3,500 feet. From 3 to 6 inches of fresh powder are expected to fall at elevations of 4,000 to 5,500 feet, while those above 5,500 feet could see up to 12 inches of snowfall, Phillips said.

With low snow levels come the seemingly inevitable worries about traffic issues across mountain roadways. Forecasters are predicting possible travel delays on the 5 Freeway through the Grapevine on Thursday.

A storm rolling into Southern California was bringing dangerous driving conditions to the Grapevine on Wednesday as Thanksgiving travel picked up.

For those heading out of town, the National Weather Service has issued a winter storm watch for much of the Sierra Nevada mountain range, beginning Wednesday afternoon and extending through early Friday for elevations above 3,000 feet. The weather service is warning of travel delays, chains may be required, and there could be road closures. Forecasters are discouraging any mountain travel beginning Wednesday night through Thursday.

Temperatures across Los Angeles County, which have been hovering in the low to mid-60s — slightly below normal — over the past week, are expected to stay chilly through Friday. But by Sunday, the mercury could creep up to 70 degrees again, Phillips said.