San Francisco broke a 132-year record low temperature, dipping to 39F (4C) on Friday morning.
Tens of millions of residents in the Golden State are under blizzard, wind and flood warnings.
The storms have blacked out nearly a million properties from coast to coast.The West Coast's main motorway, Interstate 5, was partially closed south of the Oregon border. Los Angeles - a city famed for its palm trees and sun-kissed boulevards - is under its first blizzard warning in more than three decades.On Friday people in the city marvelled at the unfamiliar sight of a snow flurry around the Hollywood sign on Mount Lee.
But elsewhere in Los Angeles, flooding trapped cars in North Hollywood, and officials warned of widespread flooding in neighbourhoods throughout the surrounding county.The National Weather Service (NWS) warned that "significant mountain snows are likely Friday night into early Saturday, with major impacts to travel and infrastructure.
"Downed trees and power lines are possible. Lower elevations may experience significant snowfall over areas where snow is unusual."The NWS warned swimmers on the state's world-famous beaches to beware of "strong rip currents and high surf".
Mountain communities can expect snowfall between 2ft and 7ft (60cm and 2.1m). Avalanche warnings have been posted in some areas.Other parts of California that will see a rare blanketing of snow include the Mojave Desert, the Santa Clarita Valley and the Inland Empire.
Earlier in the week, the storm dumped snow farther north along the West Coast, including in the city of Portland, Oregon, which saw one its snowiest days on record.