Jamie Pierre, 38, was swept over a cliff on Sunday at Snowbird Ski and Summer Resort in the Wasatch mountains about 30 miles (48 kilometres) south-east of Salt Lake City.
Pierre was snowboarding one of Snowbird's steepest slopes with a friend when he was sent cartwheeling over a cliff after he triggered the late afternoon slide, the Utah Avalanche Centre reported.
It was the season's first avalanche fatality in the US, authorities said.
"A great person, a little misunderstood at times, but anyone who knew him knows he had a heart of gold," friend Lee Cohen wrote in a Facebook posting. Cohen is a photographer for Powder magazine who lives near Snowbird.
More than a foot of fluffy snow had fallen in the mountains over the weekend where snow was already waist-deep, creating what authorities said were dangerous avalanche conditions.
"Early season is our most dangerous time of year - just the opposite of what most people think," Bruce Tremper, director of the Utah Avalanche Centre, said on Monday. "It's not anything you want to mess with."
Snowbird doesn't open for skiing until Saturday and hasn't cleared the mountain of danger. The resort had signs warning against skiing, and Pierre and his ski partner shouldn't have been on the slopes, Unified Police Lieutenant Justin Hoyal said.
"They're trespassing, technically, and it's very dangerous," Lieutenant Hoyal said Monday.Jamie Pierre's record-setting jump from 2006
Pierre set off from nearby Alta Ski Area and made his way to neighbouring Snowbird over a series of ridges. The two apparently avoided injury in one slide earlier in the day, officials said.
"With the partner watching, the victim dropped into the slope, immediately triggering the slide," the Utah Avalanche Centre said in a preliminary report posted on its website. "He was carried hundreds of feet through steep rocky terrain and reportedly went over a small cliff band and came to a stop only partially buried."
Early season in Utah always brings skiers who can't wait to hit the slopes. And because many of Utah's ski areas sit on national forest land, they can't legally keep people from venturing out even before they open. However, Snowbird owns much of the land on its resort and is allowed by the US Forest Service to ban early skiers.
Still, few skiers are ticketed or thrown off the slopes, Lieutenant Hoyal said.
Police wouldn't immediately release the name of Pierre's ski partner. Pierre's family in Minnetonka, Minnesota, didn't return a message from The Associated Press on Monday.
Pierre appeared in numerous ski films and had a legion of sponsors. He was best known for a terrifying 2006 jump off the backside of Wyoming's Grand Targhee Resort. It was a dizzying fall from higher than the Golden Gate Bridge, and garnered him a world record.
Pierre landed on his head in 12 feet (3.6 metres) of soft snow but escaped injury and promptly vowed he'd never try that again. He also had many other notable cliff jumps, including a 165-foot (50-metre) jump off Alta's signature Wolverine Cirque.
Pierre is survived by his wife, Aimee, and two children. He had lived for years in Sandy, Utah, outside Salt Lake City, but had recently moved to Big Sky, Montana, for a job."Our deepest condolences go out to Jamie's family and friends," Snowbird spokeswoman Emily Moench said. "He was a local legend, and he will be dearly missed by the community."