PORTLAND, Ore. -- Snow, ice and shivering cold blasted normally mild cities from Seattle to Las Vegas to San Francisco on Tuesday as the winter weather sweeping across the U.S. West shuttered schools, made travel treacherous and closed all roads in Yosemite National Park.
Winter storms have been hitting the West for several days and brought a surprise dusting to peaks overlooking San Francisco — the city's first notable snow in eight years. Yosemite's ski area closed, restaurants had shorter hours and shuttles were not running because of snow-covered roads.
"It's beautiful and we certainly need the snow, but we're asking people to stay indoors," park spokesman Scott Gediman said. "As the weather improves, we'll plow roads and assess the situation."
California is still recovering from a drought that led to tight water restrictions and contributed to severe wildfires.
Temperatures plunged into the teens in Seattle overnight, making roads slick, and schools throughout the area shut down for a second day. Unusual snow fell a day earlier, causing crashes and canceling flights, and lower-than-normal temperatures were expected throughout the week.
Rare snow and cold also walloped Portland, Oregon. Residents awoke to unexpected overnight snowfall that closed schools and left some higher elevation roads slick for the morning commute.
Natalie Razey, 9, of Lake Oswego, Oregon, said when the snow flurries started Monday, her teacher shared some advice for ensuring a snow day Tuesday.
"Our teacher let us do a snow dance while it was snowing at school yesterday, and I flushed ice cubes down the toilet and I put spoons under my pillow," she said during a break from sledding and snowball fights.
In Nevada, the National Weather Service reported light snow in northwest Las Vegas. More than 3 feet (1 meter) of snow has fallen at the top of some Lake Tahoe ski resorts in the last 24 hours, bringing the total to 6 feet (2 meters) since storms began Saturday.
An 80-mile (128-kilometer) stretch of westbound Interstate 80 in the Sierra Nevada reopened to vehicles with chains or snow tires.
In Utah, a semi-trailer slid off an icy highway in a canyon and hit a deputy, sending him to the hospital with serious injuries and closing the road. The unnamed Rich County sheriff's deputy is expected to survive. He was hit outside his vehicle as he investigated a different semi-trailer that had lost control and rolled off the road.
It was one of several crashes across Utah as several inches of snow fell.
Montana residents used to the cold braved the third day of subzero temperatures and biting wind chill.
Wind and fresh snowfall led officials to warn of high avalanche danger in southwestern Montana near Yellowstone National Park, and an avalanche warning was in place for the Centennial Mountains in eastern Idaho.
The region, which also includes northwestern Wyoming, was expected to receive up to 8 more inches (20 centimeters) of snow in the mountains by Wednesday.
For much of the rest of Montana, weather service officials warned of wind chills between 20 and 35 degrees below zero through Wednesday. In those conditions, frostbite can set in within 10 minutes, officials said.
Those who ventured out in downtown Helena during a break in the snow shrugged off the minus 4 degree temperature, calling it one prolonged cold snap in what's been a relatively mild winter for Montana.
"It's inconvenient, that's all," said Bruce Schwartz, a 62-year-old retiree. "I'm going to work out and spend a lot of time soaking in the hot tub."
Associated Press writers Olga Rodriguez in San Francisco; Scott Sonner in Reno, Nevada; and Matt Volz in Helena, Montana, contributed to this report.