"We're trying to scramble and get as much accomplished as possible before the next storm hits," said Deputy Kim Allyn, a spokesman for the Santa Cruz County sheriff's department, which was assembling its emergency response team.
At its height, the storm left nearly 2 million Californians without power.
At least 13 deaths were blamed on the wild weather — six died in California, two people were killed in their bed by a falling tree in Oregon and a snowboarder was killed by an avalanche at a Nevada ski resort.
The California victims included three women who died after their car was swept down a flooded creek Monday at Carlsbad, north of San Diego. Two other women with them were rescued. All were from Mexico, and were traveling on a road leading to a migrant farmworkers camp, authorities said.
Also, a man, woman and two of their adult sons died Monday night in northeastern Utah when their car skidded on slush-covered U.S. 40 and was struck by another vehicle, police said.
The region enjoyed a brief respite from the heaviest rains Tuesday, and the Russian and Napa rivers north of San Francisco fell below flood levels. But forecasters said another big storm was headed toward the state Thursday, centered just south of the Bay Area near Monterey.
Mountain dwellers in coastal Santa Cruz were warned of mudslides. Raymond Wilson of the U.S. Geological Survey said there is so much moisture in the soil that rainfall is pouring straight down hills.
In Southern California, rain caused mudslides along sections of the San Gabriel Mountains laid bare by a brush fire in September. Sludge blocked roads in some foothill towns, including La Verne and San Dimas.
A Santa Cruz County mudslide 20 years ago buried 12 houses in the early morning, killing 10 people. Storms also led to mudslides in 1998.
The U.S. Forest Service also warned that avalanche danger remained high above 6,000 feet in the Sierra Nevada, a playground for thousands of California skiers and where more than 9 feet of snow had fallen at some resorts.
Statewide, almost 100,000 customers remained without power Tuesday morning.
Even with the slight break, foul weather continued to hit Monday night and Tuesday morning. Hail pounded downtown San Francisco, accompanied by wind up to 50 mph with higher gusts. At the summit of Mount Diablo, east of the Bay, gusts reached 100 mph.
A quarter-inch of snow fell in the mountains above San Jose, and lightning knocked out a National Weather Service radar station high in the Santa Cruz mountains.
Rainfall records were toppled across California on Monday. In downtown Los Angeles, a 62-year-old mark was broken when nearly 2 inches fell in 24 hours; in San Francisco, 2.1 inches were recorded, easily breaking the record of 1.36 inches set in 1962.
In Nevada, 1.29 inches fell at the Reno airport, doubling the mark set in 1957. In western Nevada, the storm damaged homes, closed schools and knocked out power to thousands.
Twelve Carson City families were left homeless after wind ripped the roof off an apartment complex.
"I've lost my livelihood, but I'm more than sorry for the poor tenants who have to find somewhere else to live," said property owner Ron Smiley.
By Anna Oberthur