A slow-moving winter storm intensified over California on Friday local time, triggering the first blizzard warning in parts of the Los Angeles area in 30 years and creating the extraordinary sight of snowflakes swirling around the iconic Hollywood sign.
Key points:
- A low-pressure system driven from the Arctic is causing freezing winter storms in parts of the United States
- LA residents witnessed snow falling on the Hollywood sign on Friday, while San Francisco broke a 132-year-old temperature record
- Experts say powerful winter storms, interspersed with extreme heat and dry spells, are symptoms of climate change
Snow and freezing rain pushed into the state from the north, where it dumped about 25 centimetres of powder on Portland, Oregon, earlier in the week.
California's snow was heaviest in the Cascades, Sierra Nevada and coastal mountains.
But even residents in the lower-elevation foothills of California's central coast and the San Francisco Bay area awoke on Friday morning to several centimetres of snow.
"The last time we saw snow like this in the low elevations was in 2011," said Sarah McCorkle, a National Weather Service (NWS) meteorologist in Monterey, California.
"It's a relatively rare event."
San Francisco also broke a 132-year record for the lowest February 24 temperature ever documented, as the mercury dipped to 4 degrees Celsius on Friday morning, beating the previous record set in 1891.
A massive low-pressure system driven from the Arctic was responsible for the unusual conditions, said Bryan Jackson, a forecaster at the NWS Weather Prediction Center in College Park, Maryland.
In a sight that must have delighted many Los Angeles residents, snowflakes even fell around the Hollywood sign atop Mount Lee in the hills above the city, known for its sunny days and palm trees.
At an elevation of 457 metres, the sign — with its giant, white-block lettering visible for miles around the city — was close to the threshold for the formation of snow during the storm, Mr Jackson said.
Craig Robert Young, an actor who starred in the television series Charmed and The Last Ship, lives in the Hollywood Hills within eyeshot of the famed sign.
He said he was amazed to see snow swirling there.
"I moved here from the United Kingdom 20 years ago, and haven't seen snow since," said Young, 46.
"I actually had a snowball fight. It brought me back to my childhood."
In nearby San Bernardino County, the sheriff's office posted a video clip on Twitter showing deputies lying in the snow, flapping arms and legs to make "snow angels", while also urging residents to stay off roads.
'We're at the mercy of the skies'
Snowy road conditions and high winds prompted the California Highway Patrol (CHP) and state transportation officials to close the Interstate 5, a major highway connecting Los Angeles to northern parts of the state, along a 64-kilometre mountain stretch known as the Grapevine.
It remained unclear how long the closure would last, according to CHP officer Anthony Daulton.
"We're at the mercy of the skies right now," he said.
A separate storm that clobbered the US Plains, Midwest and Great Lakes regions earlier this week blew out to the Atlantic on Friday after passing over New England, the weather service said.
More than 750,000 homes and businesses, mostly in Michigan, remain without electricity.
Even before the latest storm, much of California has experienced an unusually rainy, chilly winter, starting with a spate of deadly "atmospheric river" storms that unleashed widespread flooding, felled trees and triggered mudslides in a state long plagued by drought and wildfires.
Powerful winter storms, interspersed with extreme heat and dry spells, are symptoms of climate change, experts say, and growing more frequent and intense.
Reuters