More rain, snow are in California’s stormy forecast. What to expect this weekend

Another cold, wet storm is brewing off the California coast, likely bringing more rain and snow across the Southland this weekend — and officials are warning it could be enough to spur minor flooding and mudslides.

The low-pressure system is expected to first bring rain to the Central Coast on Friday, expanding south over the next 72 hours and bringing rain, snow and gusty southerly winds across Southern California.

“We are expecting some heavy rain at times and quite a bit of snow in the mountains,” said Mike Wofford, a National Weather Service meteorologist in Oxnard. “It’s going to be a stormy period.”

When to expect rain?

For Los Angeles County, rain is expected to begin Friday evening, kicking off what forecasters say will be a pretty steady downfall through Saturday night.

“For the most part, it should be raining all Friday night and all of Saturday,” Wofford said.

The rain could linger through Easter Sunday, when showers and thunderstorms are possible, Wofford said. By Monday, most of the rain should have moved out of the area.

How much is coming?

With strong competition from prior storms this winter, this system isn’t shaping up to be the strongest this season, but forecasters say it is still colder and wetter than a typical, late-spring Pacific storm.

Most of Southern California can expect 1 to 2 inches of rain, though some foothill and mountain regions could see up to 4 inches, Wofford said, depending on thunderstorms and rain rates.

There’s snow too

At about 5,000 feet of elevation, the rain will turn to snow — and a lot of it.

“We could have a couple feet of snow. The higher you get in elevation, the higher the amounts will get,” Wofford said.

More than a foot of snow is expected in the San Bernardino County mountains above 5,500 feet, with up to 3 feet likely at the highest peaks. Lower elevations in the mountains of Los Angeles County could get 2 to 6 inches of snow, although Wofford said it’s unlikely the Grapevine will see any accumulation.

What are the risks?

While the rain totals aren’t concerning at face value, the storm is following a winter of heavy rains that have continued to wreak havoc across the region.

“We have had a lot of rain this season, and we still have active slides … so it’s not really going to take a whole lot to create some additional hazards across the area,” Wofford said. “In terms of standard street flooding and mud and rock slides in the mountains and foothills, we’re going to see all of that this weekend.”

Among the active landslides is one at Topanga Canyon Boulevard, which has been closed indefinitely in both directions between Pacific Coast Highway and Grand View Drive since March 12. According to an update this week from the California Department of Transportation, that landslide is “still moving and too dangerous to clear,” with the additional rain this weekend expected to worsen conditions.

The National Weather Service said there’s a moderate risk for significant flooding across the region, as isolated storm cells could bring rain rates of three-quarters of an inch per hour.

What’s driving all this rain?

This system is kicking off a wetter pattern, driven in part by a strong El Niño winter, and is expected to continue for at least the next week.

It’s picking up moisture from the Pacific Ocean before it comes ashore later this week.

“It’s a little stronger than our typical storm system, a little colder,” Wofford said. “The impacts locally will be a little more than what we’re typically used to.”