6 backcountry skiers found alive, 10 missing after avalanche near Donner Pass in Sierra Nevada, California: officials

NEVADA CITY, Calif. — Six backcountry skiers were found alive and 10 others were still missing Tuesday in an avalanche in Northern California during a powerful winter storm moving through the state.

Search and rescue crews were dispatched to the Castle Peak area, northwest of Lake Tahoe, after someone called 911 to report an avalanche with people buried.

Authorities combed the area of Castle Peak, which is northwest of Lake Tahoe.

The Nevada County Sheriff’s Office received a 911 call at about 11:30 a.m. from someone reporting an avalanche with people buried, said Ashley Quadros, a spokesperson.

The sheriff’s office, the sheriff’s Search & Rescue team and a crew with the California Department of Forestry and Fire Protection were combing the area of Castle Peak, which is northwest of Lake Tahoe, Quadros said.

“It has been reported that a group of backcountry skiers was involved in the incident, with several members of the party missing at this time,” the sheriff’s office wrote in a Facebook post.

A Sierra Avalanche Center official told ABC News that the group of more than a dozen backcountry skiers was leaving an overnight hut trip at Frog Lake Hut.

At least 10 of them were caught in the avalanche, but it’s unclear how many were fully buried, partially buried, or injured.

Officials say the group reported three members were actively working to dig out victims.

California is being walloped this week by a powerful winter storm carrying treacherous thunderstorms, high winds and heavy snow in mountain areas.

According to the Sierra Avalanche Center of the Tahoe National Forest based in Truckee, the area in the Central Sierra Nevada, including the Greater Lake Tahoe region, was facing high avalanche danger in the backcountry with large slides expected to occur Tuesday and into Wednesday.

The dangerous conditions were caused by rapidly accumulating snowfall piling on already fragile snowpack layers coupled with gale-force winds.

Several ski resorts around Lake Tahoe were fully or partially closed due to the extreme weather. The resorts along highways have avalanche mitigation programs and were not expected to be at as high of a risk as the backcountry where travel in, near, or below the avalanche terrain was strongly discouraged, the center said.

“It’s particularly dangerous in the backcountry right now just because we’re at the height of the storm,” said Brandon Schwartz, Tahoe National Forest lead avalanche forecaster at the center.

Experts rely on people who witness an avalanche or its aftermath to know when and where an avalanche has occurred, Schwartz said.

Castle Peak, a 9,110-foot (2,777-meter) peak in the Donner Summit area of the Sierra Nevada, is a popular backcountry skiing destination. In the nearby town of Soda Springs, at least 30 inches (76 centimeters) of snow had fallen in the last 24 hours, according to the Soda Springs Mountain Resort.

Forecasters said the western slope of the Sierra Nevada in northern Shasta County – including portions of Interstate 5 – and parts of the state’s Pacific Coast Range could see up to 8 feet (2.4 meters) of snow before the storm moves through late Wednesday.

RELATED: Snowmobiler dies after avalanche in California’s Sierra Nevada

The storm wreaked havoc on roadways spanning from Sonoma County to the Sierra Nevada. Traffic was halted temporarily in both directions on I-80 near the Nevada state line due to spinouts and crashes, the California Department of Transportation reported.

In January, an avalanche in the region buried a snowmobiler in snow and killed him, authorities said. Each winter, 25 to 30 people die in avalanches in the U.S., according to the National Avalanche Center.

This story is developing. Check back for updates.