Cold storm to produce travel-disrupting mountain snow in Southern California

Another storm was already slicing across Southern California, but AccuWeather meteorologists say it is set to play out much differently than others so far this winter. While the upcoming storm is expected to have limited moisture, it can pack enough snow at the lower elevations, as well as locally gusty showers and thunderstorms, to cause travel disruptions.

Following multiple atmospheric river events from late 2022 into the start of 2023 that hacked away at the state's long-term drought at the cost of deadly flooding and mudslides, Pacific storms during much of the latter half of January have generally tracked inland across the West but have missed California. These storms are known in the meteorological community as "inside sliders."

AccuWeather meteorologists say the latest inside slider will track farther to the south and west than its predecessors, which will bring more impact to California. The storm only brought 0.02 of an inch of rain to San Francisco and 0.11 of an inch to Sacramento. However, rainfall ramped up farther south. Chilly gusty winds will be the main impact of the storm in the northern two-thirds of the state into Monday night.

By midday on Monday, Downtown Los Angeles had picked up close to three-quarters of an inch of rain, which was among the greatest in the state, outside of remote mountain locations in Southern California.

Showers of rain and snow, along with gusty winds, will continue over Southern California and other parts of the Southwest into Tuesday.

"This storm will not tally up massive amounts of rain and mountain snow like the events that occurred earlier in the month, but that does not mean it will not have its own set of hazardous conditions," AccuWeather Meteorologist Brandon Buckingham said.


AccuWeather experts say snow in Southern California could be particularly troublesome with this event, especially compared to prior storms this winter that have failed to bring much snow to the intermediate elevations in this part of the state.

"Very chilly air associated with this storm is expected to drop snow levels below 3,000 feet in some places, which can lead to a couple of slushy inches across places like the Grapevine in Southern California. Higher up in elevation, snowfall totals can exceed a half of a foot above 5,000 feet," Buckingham said.

Snow levels this low are below the passes along Interstates 5, 8 and 15, which can result in treacherous travel from later Sunday night through Monday night. Accidents and road closures will be possible.

"Some of the hills surrounding Los Angeles and San Diego could experience some snowflakes," AccuWeather Senior Meteorologist Alex Sosnowski said.

The vigorous nature of this storm can also trigger locally gusty to severe thunderstorms, forecasters say.

"This is the type of setup that can trigger locally severe thunderstorms, packing strong wind gusts, brief intense downpours and hail in the Los Angeles, San Diego and Palm Springs, California, areas," Sosnowski said.

Limited moisture will reach the Four Corners region with this storm, but there can be a few snow showers in the high terrain and stray rain showers at the lower elevations.

In terms of temperatures, the mercury can plunge 10-20 degrees Fahrenheit below normal across Southern California and the Desert Southwest early this week. Typical highs around the end of January and the start of February range from the upper 50s in Redding, San Francisco and Sacramento to the upper 60s in Los Angeles and San Diego and the lower 70s in Palm Springs.

"Following the storm, another round of sub-freezing temperatures are expected across a majority of the San Joaquin Valley early this week. Farmers will once again have to monitor temperature trends carefully to see if the potential exists for any crop damage," Buckingham said.

The next storm to impact California may not arrive until the end of the week at the earliest.

Want next-level safety, ad-free? Unlock advanced, hyperlocal severe weather alerts when you subscribe to Premium+ on the AccuWeather app. AccuWeather Alerts are prompted by our expert meteorologists who monitor and analyze dangerous weather risks 24/7 to keep you and your family safer.