Snow has closed the Grapevine in both directions Friday.
The closure is at the Grapevine summit, and officials said they don't know when Interstate 5 will reopen.
"A cold storm system will push southward from the Gulf of Alaska across the forecast area today through tonight. Snow levels will plummet to 2000-3000 feet today.
Elevations above 4000 feet can expect between 6 and 10 inches of snow, with lesser amounts across the Santa Barbara mountains and lower elevations," the weather service said in a statement.
-- Los Angeles Times