The Grapevine section of the 5 Freeway north of Los Angeles was closed early Saturday as a powerful winter storm slammed Southern California.
Both sides of the freeway were closed through the Tejon Pass in northern Los Angeles County. The closure will continue until conditions improve.
More than a foot of snow fell Friday by midday at the corridor's higher elevations, Caltrans said. More snow blanketed the area overnight.
"Do not travel through the mountains if you do not need to," said NBC4 forecaster Shanna Mendiola.
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A cold storm is expected to bring more snow and rain throughout Friday and into Saturday. Mountains in Los Angeles County are under a blizzard advisory for the first time since 1989.
Blizzard warnings, indicating snow or blowing snow, reduced visibility and sustained winds of 35 mph or greater, will be in effect for Los Angeles, Ventura and San Bernardino county mountains through Saturday afternoon.
Areas under the blizzard warning include, Mount Wilson, the Grapevine section of the 5 Freeway, Acton, Mount Pinos and Frazier Park. Travel is highly discouraged in Southern California's mountains.
Two to 5 feet of snow are expected above 5,000 feet by Saturday as the storm continues to hammer the region. Some areas could get as much as 7 feet.
Snow accumulations of 6 to 12 inches are possible by Saturday night at elevations as low as 2,000 feet.