Torrential rains trigger mudslides, flooding in California
Several inches of rain have been reported in parts of California already as the storm drenches the region its first of two days' worth of expected impacts.

Mudslide along California Highway 70 on Dec. 13, 2021.
(CalTrans)
SAN FRANCISCO -- A potent atmospheric river is pushing flooding rains across parts of the Bay Area and central California while heavy snows are pummeling the Sierra Nevada Mountains.
Several inches of rain have been reported in parts of California already as the storm drenches the region its first of two days' worth of expected impacts.
The heavy rain has triggered some mud and rock slides along California highways.
Rocks and mud blocked State Highway 70 in the Feather River Canyon near the Butte and Plumas County line

Mudslide along California Highway 70 on Dec. 13, 2021.
(CalTrans)
Another minor slide littered debris on Felton Empire Road:
In San Mateo County, the storm brought some street flooding and strong winds.
Water had covered parts of State Highway 92 in Spanish Town, according to Cal Fire:

Flooding along California Highway 92.
(CalTrans)
And winds toppled scaffolding in Downtown San Mateo along S. El Manio Real Road.

In San Mateo, Calif., southbound S. El Camino Real from 3rd Ave to 5th Ave closed due to downed scaffolding in the roadway.
(San Mateo Police Department)
In Half Moon Bay, flooding swamped a credit union:
Up in the mountains, it was heavy snows that was expected to tally 2-3 feet below 7,000 feet and as much as 3-6 feet or more above 7,000 feet.
Already the University of California Berkeley Snow Lab in the Sierras had 18.7 inches of snow in 24 hours and nearly two feet of snow over a 48 hour period with heavy snow still falling.
Major snowstorm results in hazardous weather for Sierra Nevada mountains
Video shows heavy snow coming down at UC Berkeley’s Central Sierra Snow Laboratory. A major storm is likely to bring 3-6 feet or more of snow for areas of the Sierra Nevada mountain range.