The first in a new series of winter storms soaked much of California — snarling commutes, downing trees and dumping heavy snow in the mountains.
Rain began to taper off about 7 a.m. as the storm moved east toward San Bernardino, Stuart Seto with the National Weather Service told KPCC. The flood advisories issued for Orange County as well as a flash flood watch in L.A. County were cancelled before 9 a.m.
Thursday’s storm brought 1.5 inches of rain to Ventura County, 0.75–1.25 inches to L.A. County and 1 inch to the San Fernando Valley. The next storm system should hit the area shortly after midnight Thursday into Friday morning, prompting new winter weather and high surf warnings, according to the National Weather Service.
Surf conditions along piers and harbors would become a big issue with this week’s storms, reaching up to 15-foot swells in L.A., Orange and Ventura counties, Seto said.
L.A. should prepare for a cloudy next few days, leading up to an even bigger storm this weekend, Seto said. A storm system expected to come through the area on Sunday could bring up to 3 inches of rain to the greater L.A. area and several more inches of snow to areas higher than 5,000 feet, he said.
In Southern California's Santa Monica Mountains, rain was falling at rates of up to a half-inch per hour. The Hollywood Reservoir got almost three-quarters of an inch of rain, said Curt Kaplan, a meteorologist with the National Weather Service.
Two more storms are approaching the region, and rain is in the forecast again overnight. The heaviest rainfall of these systems is expected late Saturday until Monday. As for snowfall, it will likely be the heaviest late Friday night into Saturday and snow could fall on the Grapevine, Seto said.
Cities along the coast will be under a high surf warning through Monday, as large swells with the potential to cause waves up to 16 feet sweep through. According to the service, the region could get the highest surf seen in recent years, brewing dangerous ocean and beach conditions.
Forecasters also warn that mud and debris flows could occur as heavy rains fell on wildfire burn scars east of Los Angeles.
That includes Santa Clarita, where more than 38,000 acres burned last year in the Sand Fire. Concrete barriers are installed in the burn zone, and sandbags are available at fire stations, said Carrie Lujan with the city of Santa Clarita.
Lujan said maintenance crews will work 12-hour shifts.
"They will be driving around the city evaluating areas prone to flooding, especially the recent burn areas, and should there be any mud flow they'll be ready to clear any mud and debris off the roadways," she said.
Last month's rains caused some debris to wash out into the streets, but it was cleaned up quickly, Lujan said.
Traffic was snarled on the southbound 5 Freeway early Thursday after a crash involving a big rig. Truck lanes would be blocked for about three hours, according to the California Highway Patrol.
Up to 3 inches of rain was expected through Thursday in parts of the San Francisco Bay area.
Flood advisories and watches are posted on the far north coast. Winter storm warnings are in place across the Sierra Nevada.
The National Weather Service office in San Diego warns that five-day rainfall totals will likely be substantial. Combined rainfall totals for all three storms could be three to six inches for coastal and valley areas, and possibly up to nine inches in some foothill and mountain areas.
Storms are expected to bring precipitation across California into early next week, with brief breaks between systems.
This story has been updated.