Three skiers killed in a Washington state avalanche on Sunday were highly experienced at backcountry skiing, according to media reports, and one was the head judge of the Freeskiing World Tour, a competitive circuit for extreme skiers in the United States, Canada and South America.

The three, ski tour judge Jim Jack, Chris Rudolph and John Brenan, were among a group of a dozen or so skiers who were attempting to ski down a slope near the Stevens Pass ski area in the Cascade Mountains, about an 80-mile drive from Seattle. Among the group were staffers of both ESPN and Powder magazine, who identified the victims and gave accounts of the incident.

Powder magazine senior editor John Stifter said the avalanche was triggered by Jack, who was the seventh skier to head down the slope, which is outside the borders of the resort and its groomed ski runs. Jack triggered a “slab avalanche,” according to Stifter.

The U.S. Forest Service’s National Avalanche Center says dry slab avalanches are the most deadly form of avalanches.

"The slab avalanche is more like a large surface plate that comes off the mountainside and crumbles into blocks as it falls. The boundaries of this plate of snow begin as fracture lines or cracks visible on the snow surface. Unfortunately they may not be visible seconds before the slide," David Sauer writes in an article archived by Avalanche-Center.org.

“Fractures can propagate through the snow at speeds of 50-200 mph. Victims … rarely have a chance to escape,” the Forest Service's Avalanche Awareness website says.

On Sunday, the chunks of that snow slab sped down the mountain, swallowing up Jack and other skiers, including those who’d skied off the slope about 300 feet below the top and into what they thought was a safe area in the trees.

Rudolph, Brenan and professional skier Elyse Saugstad were in that group, according to the accounts of Stifler and ESPN freeskiing editor Megan Michelson.

Saugstad told the Seattle Times she heard another member of the party shout "Avalanche!"

"The next thing I knew I was taking more than a 2,000-foot ride down an avalanche, tumbling and turning and tossing the entire way," the Times quoted her as saying.

The avalanche carried Jack, Rudolph, Brenan and Saugstad 2,000 feet to 3,000 feet down the slope. Saugstad was able to deploy an airbag she wore for safety in these circumstances and it kept her head and arms above the snow.

"It kept her atop the avalanche and basically saved her life," John Gifford, general manager of the Stevens Pass ski area, told CNN affiliate KIRO-TV.

See how the airbag works

The other three were unable to be revived after they were pulled from the snow pile, which was about 20 feet deep at the bottom of the slide, according to local news reports.

"The debris pile at the bottom was massive," Michelson said in the ESPN report.

"I believe my partial burial and survival was on account of the inflation of my ABS Avalanche Airbag Backpack," Saugstad said in a statement on her website.

She also said her "condolences and sympathies are with the families and victims of the avalanche incident."

All, Saugstad said, were experienced in backcountry skiing.

Jack had been involved in the World Freeskiing Tour since its inception more than two decades ago, according to an ESPN report from November, first as a competitor before he became a judge. In the report, he said he turned to judging about 10 years ago after “I shattered my face while competing at Kirkwood,” one of the U.S. stops on the tour.

In the same ESPN interview, he said the tour emphasized safety.

“We do not want to find ourselves rewarding or encouraging dangerous or uncalculated decisions in skiing,” Jack was quoted as saying.

The avalanche danger in the Cascades was listed as considerable to high on Sunday, according to the Northwest Weather and Avalanche Center, after the area got more than two feet of snow in the previous 24 hours. But among the skiers in the group, “the consensus was that they could manage the hazard if they followed proper protocol,” according to the Powder report, citing Stifter.

On a page on about.me, Rudolph calls himself the "director of marketing, culture and stoke" at Stevens Pass. Rudolph was called “a seasoned backcountry skier and pro-wrangler for high-profile video shoots," according to a Ski Area Management Magazine article quoted on about.me.

Doug Schnitzspahn, editor-in-chief of Elevation Outdoors magazine, told CNN that a kind of group-think takes over in these situations, with skiers wanting to be there with their peers.

"You think, 'All these people are either professional skiers or they knew what they're doing, they are out here,'" he said. "You're trained to make certain decisions, but it's not always humanly possible. If I had been there, I would have skied that line with those guys. That's what shakes me up."

The Freeskiing World Tour planned a memorial for Jack on Monday afternoon at the Snowbird Ski and Summer Resort in Utah, according to the tour’s Facebook page.

“All friends, family, and public welcome to celebrate the life of our brother, and amazing freeskiing spirt,” the posting said.

Posters mourned Jack.

“So sad! Jim, you made a difference in a lot of skiers' lives!!!” wrote one.

“This is unreal. Jim Jack, you will be so missed,” wrote another.

The tragedy was the second to hit the skiing community this year.

Exactly a month before the three skiers died in the avalanche, freestyle skier Sarah Burke died from injuries suffered in a training accident in Utah.

"More terrible news. Our thoughts and prayers go out to the family and friends of the victims," said a posting on Powder magazine's Facebook page.