The strongest storm series of the winter season is headed to California and could dump several inches of snow in mountain ranges across the state, weather forecasters reported March 10.

Southern California residents were enjoying one more sunny day Monday before two storms were expected to drop rain and snow, and bring much lower temperatures, starting Monday night, according to the National Weather Service.

The region could also get thunderstorms Wednesday afternoon, the weather service warned.

“Any thunderstorms that develop will produce brief heavy rain, gusty winds, steep seas and possibly even waterspouts,” the National Weather Service’s Oxnard office warned Monday.

A low-pressure weather system Monday night could bring rain to Los Angeles, Ventura, and Santa Barbara counties, with some mountain snow possible. The system that arrives Wednesday and Thursday is expected to bring more significant heavy rainfall, the weather service reported on social media Monday afternoon.

National Weather Service forecasters expect the southern region to receive up to three inches of snow above 4,500 feet Monday and Tuesday, and another one to two feet of snow above 6,000 feet Wednesday and Thursday.

The same region could also see up to a half-inch of rain Monday and Tuesday, and another two to four inches Wednesday and Thursday.

The weather service issued a flood watch for lower-lying areas and winter storm watch for the mountains.

“Travel could be very difficult to impossible,” the weather service stated in an alert Monday.

The University of California–Berkeley, Central Sierra Snow Lab reported Monday that the winter storm could bring the Lake Tahoe area several feet of snow.

“The biggest storm window of the season is upon us,” the snow lab located at Donner Pass near Lake Tahoe, wrote on social media. A consistent stream of storms over the next 7-10 days has the potential to bring us over eight feet of snow, the lab reported.

A motorist tries to escape the mud-covered intersection at Sunset Boulevard and Pacific Coast Highway, near the Palisades Fire zone, during a storm in Malibu, Calif., on Feb. 13, 2025. (Agustin Paullier/AFP via Getty Images)

“Wednesday and Sunday are looking like the biggest storm days,” the lab added. “It’s too early to lock in estimates but we’ll be keeping a close eye on it.”

Rain is also expected to return to San Diego County with heavier, wet conditions by Wednesday. The heaviest precipitation is expected to arrive Thursday morning, according to the National Weather Service.

The upcoming rainfall was expected to arrive in two storm systems. The first could hit Wednesday morning and the second was expected to be a wetter system that arrives Thursday and Friday, the weather service’s San Diego office posted on social media Monday.

The city of San Diego started placing “no parking” signs Monday in low-lying and other areas susceptible to flooding. City workers also started cleaning storm drains and inlets with a history of debris buildup.

“We know how impactful heavy rain can be, and we want to ensure that both the city’s stormwater infrastructure and our residents are ready to face the weather,” said Stormwater Department Director Todd Snyder.