(CNN) -- More than 10 feet of snow could fall on California mountains by Sunday and winds could reach the strength of an extremely strong hurricane as powerful winter storms move through the state.
Workers fill sandbags in Malibu, California, Thursday as residents prepare for potential mudslides.
"Travel is not advised in the mountain areas this weekend. It could be a life-threatening situation for you," CNN meteorologist Jacqui Jeras said Friday.
"The combination of heavy snow and powerful winds will likely cause frequent whiteout conditions at the highest elevations," National Weather Service forecasters said. "Travel over the higher passes will be very difficult, if not impossible, at times between Friday evening and Saturday morning."
Winds in the mountains could gust to 145 mph, forecasters said, the strength of a Category 4 hurricane. A Category 4 can inflict extreme damage.
In Mammoth Lakes in the eastern Sierra Nevada, locals stocked up on supplies, waiting more than an hour in line at the grocery store, resident Barbara Sholle told The Associated Press.
Even in lower elevations, gusts could reach 60 mph, the National Weather Service said. "Be alert for flying debris," the service warned. "Secure all doors and windows and stay indoors if possible."
At 6 a.m. PT Friday, wind gusts of 56 mph were recorded at Redding in the northern part of the state.
Yukiah and Arcata, both in northern California, reported almost an inch of rain in three hours Friday morning and more was on the way.
Up to 10 inches of precipitation was forecast for lower elevations.
Sacramento could see as much as 3 inches of rain Friday, CNN affiliate KCRA reported.
In Kern County, forecasters said that more rain could fall this weekend than fell in all of 2007, the county's driest year since 1961, CNN affiliate KERO reported.
In Southern California, forecasters warned it could be the most significant rainfall since January 2005. Flash-flood watches were in effect around Los Angeles and San Diego, and the possibility of mudslides loomed for hillsides scorched bare by wildfires last year.
Authorities advised homeowners in those areas to have plenty of sandbags on hand and watch for signs of flooding, The AP reported.
In Orange County, the Conservation Corps on Thursday was placing gravel-filled bags along an area burned last fall, according to AP.
Gov. Arnold Schwarzenegger ordered the state Office of Emergency Services to prepare for the bad weather.
"The state is expecting a powerful series of storms that could produce blizzard conditions in the higher elevations of the Sierra, with wind gusts of more than 100 mph and 8 to 10 feet of snow forecast at above 7,000 feet," a news release from Schwarzenegger's office said.
The weather disrupted air traffic Thursday. Flights into San Francisco were delayed more than two hours Thursday, affecting air traffic throughout the country, the Federal Aviation Administration said. Shorter delays were reported in Los Angeles.
In addition to the wind, rain and snow, the storm will bring high surf and coastal flooding, forecasters said. Ocean tides could swell up to 30 feet, prompting the Coast Guard to warn boaters not to venture out of port, AP reported.
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