Pedestrians cross California Street in San Francisco on Friday. The National Weather Service has issued blizzard warnings for the Sierra Nevada and Southern California mountain ranges, where as much as 5 feet of snow was expected. Jeff Chiu/Associated Press

LOS ANGELES — Heavy snow and rain pounded California and other parts of the West on Friday in the nation’s latest winter storm, while thousands of people in Michigan suffered in freezing temperatures through extended power outages wrought by one of the worst ice storms in decades.

The storms have blacked out nearly 1 million homes and businesses from coast to coast, closed major roads, caused pileups and snarled air travel. More than 300 flights were canceled and over 5,000 were delayed Friday across the U.S., according to FlightAware.com.

The National Weather Service warned of a “cold and dangerous winter storm” that would last through Saturday in California. Blizzard warnings were posted in the Sierra Nevada and Southern California mountain ranges, where as much as 5 feet of snow was expected.

“Simply put, this will be a historic event for the amount of snow over the higher peaks and lower elevation snow,” according to the regional weather office.

Interstate 5, the West Coast’s major north-south highway, was closed south of the Oregon border as snow fell to the floor of the Sacramento Valley and in a high mountain pass north of Los Angeles, where blizzard warnings were in effect. Avalanche warnings were posted in some areas, and flash flood warnings were issued for Los Angeles and nearby coastal areas until Friday night.

In Michigan, hundreds of thousands of people remained without power Friday after a storm earlier this week coated power lines, utility poles and branches with ice as thick as three-quarters of an inch.

Annemarie Rogers had been without power for a day and a half in Grosse Pointe Farms, Michigan. She sent two kids to stay with relatives and put extra blankets on the bed to try to keep warm.

“It’s kind of miserable,” she said. “We do have a gas fireplace that’s keeping us warm in one room. There’s some heat generating from the furnace, but with no electricity to the blower it’s not circulating well.”

At one point, more than 820,000 customers in Michigan were in the dark. By Friday, that was down to under 700,000, most in the state’s populous southeastern corner around Detroit. But promises of power restoration by Sunday, when low temperatures were expected to climb back above zero, were of little consolation.

“That’s four days without power in such weather,” said Apurva Gokhale, of Walled Lake, Michigan. “It’s unthinkable.”

Tom Rankin said he and his wife were unable to reach his 100-year-old mother-in-law Friday morning by phone. The couple drove to her home in Bloomfield Township, Michigan, to find her in bed “with a whole lot of blankets,” Rankin said, adding they helped her to their car, planning to ride out the outage at another relative’s home.

“We’ve not had an ice storm in the last 50 years that has impacted our infrastructure like this,” said Trevor Lauer, president of Detroit-based DTE Electric.

At least two people have died in the storms. A Michigan firefighter died Wednesday after coming in contact with a downed power line, while in Rochester, Minnesota, a pedestrian died after being hit by a city-operated snowplow.

Much of Portland, Oregon, was shut down with icy roads not expected to thaw until Saturday after the city’s second-heaviest snowfall on record this week – nearly 11 inches.

Tim Varner sat huddled with blankets in a Portland storefront doorway that shielded him from some of the wind, ice and snow. Local officials opened six overnight shelters but the 57-year-old, who has been homeless for two decades, said it was too hard to push a shopping cart containing his belongings to get to one.

“It’s impossible,” he said. “The snow gets built up on the wheels of your cart, and then you find slippery spots and can’t get no traction. So you’re stuck.”

Not all were dismayed by the winter weather. In the San Francisco Bay Area, hundreds of people drove up to 2,500-foot Mount Tamalpais to play in the snow – a rarity in the area.

San Francisco resident Shankar Krishnan woke up at 4 a.m. and headed out hoping to see snow for the first time in a long time.

“It feels awesome. It’s like the trees are all frosty. There’s snow on the ground. There’s snow coming down from the sky,” Krishnan said. “It’s beautiful out here.”

In Southern California, flood watches and warnings were in effect through Saturday afternoon for some coastal regions and valleys, with the potential for rainfall causing flooding and debris flow in some areas burned by wildfires in recent years. In the flash flood warning area, between 3 and 6 inches of rain had fallen by Friday afternoon with another 2-4 inches expected.

Evacuation warnings were issued in Ventura County for four areas considered unstable after being hit hard by storms last month.

Parts of Interstate 80 in California and Wyoming closed, including about a 70-mile stretch over the top of the Sierra Nevada linking California and Nevada. Some schools in Nevada and northern Arizona were closed, and a Major League Soccer season-opening game in Southern California was postponed.

The storm has added to major precipitation from December and January “atmospheric rivers” that improved California’s drought outlook, but authorities who allocate water to farms, cities and industries remain cautious because of a recent history of abrupt changes in hydrologic conditions.

The weather service said temperatures could drop far below normal in the region, posing a special risk to homeless people.