Scott Brennise looked back Sunday, scanning the snow for any sign of his friend.
Seconds before, he and two other local residents, Mike and Rusty Zimmerman, were charging up a snow-covered hill on their snowmobiles about six miles south of the Marapos Creek trailhead in Rio Blanco County.
Then, a heavy load of snow came hurtling down on them from the hill's crest.
The swell had swept Brennise to safety into a patch of trees below.
Mike, however, wasn't so fortunate. He had been directly in the slide's path and hadn't escaped.
In the moments after the biggest snow slide Brennise had ever seen, one urgent thought ran through his mind.
"I knew I had to find him," Brennise said.
Sunday's avalanche took place south of Hamilton. Brennise, who had ridden snowmobiles since he was a child, had traversed the hill multiple times.
He'd also seen a few snow slides, he said, but nothing like what he experienced Sunday.
Then again, this winter hasn't been a usual one.
Layers of weak, unstable snow followed by sustained, heavy snowfalls have created avalanche-prone conditions in portions of the western United States and southwest Canada, said Art Judson, a retired 23-year U.S. Forest Service avalanche specialist.
Judson, a Steamboat Springs resident, continues to gauge avalanche conditions around Routt County.
This year's snowpack has had lasting and lethal effects on snowmobile riders across North America. Eleven people have died this month in avalanches across the western U.S., according to information gathered by Avalanche.org, a site sponsored in part by the American Avalanche Association.
An additional seven snowmobilers have been killed in two avalanches that occurred Sunday in the Canadian province of British Columbia, the Web site reported. Three people escaped the slides and one is still missing.
That avalanche conditions formed over such a large area this year is rare but not unheard of, Judson said.
"In bad years you see it, and this is one of those," he added.
'I knew it was serious.'
Brennise had seen signs Sunday indicating an avalanche was imminent moments before it occurred.
Snow had drifted at the top of the slope, creating a heavy ledge, or cornice. He could see the crack in the snow - a subtle, but telltale sign of a developing avalanche.
Brennise, who directly was in the slidess path, pointed his sled down slope to a clearing in the trees below.
Before he turned, though, he looked back to gauge Mike's position.
"I didn't know if he was going to be in trouble or what, but I knew that he was going to be in the middle of the slide," Brennise said.
Then the avalanche hit.
He estimated that eight to 10 seconds elapsed from when he first noticed the cornice to when the avalanche ended.
Fortunately, it didn't take long for Brennise to locate Mike.
Mike was buried headfirst in the snow, with his feet sticking up out of the slide's debris. Brennise ran over to where his friend was submerged and began digging him out with his hands. As he did so, he called for Rusty to bring a shovel.
Both men remained calm, despite the seriousness of the situation.
"Neither of us panicked," Rusty said. "We knew what we had to do, and we went about doing it."
Freeing Mike from the snow was an arduous task. He had been buried at an angle, with his head immersed four feet under the snow.
About seven minutes passed before Rusty and Brennise uncovered Mike's face and removed his helmet. By that time, Mike was unconscious.
To make matters worse, his snowmobile was still running and had filled his lungs with carbon monoxide.
"I knew he was breathing, but he was having a real hard time," Brennise said. "It sounded to me like he had fluid in his lungs.
"At that point, I knew it was serious."
Shortly after Rusty and Brennise pulled him out of the snow, Mike regained consciousness.
Brennise then called 911, fearing Mike had internal injuries.
After ensuring Mike could move his extremities, they loaded him on a snowmobile. The pair drove him the six miles back to the trailhead, where they were met by a waiting ambulance.
Mike was taken first to The Memorial Hospital in Craig and later was flown to University Hospital in Aurora. He has since been released and has returned to Craig.
Being trapped upside-down caused Mike some pulmonary problems, Rusty said, adding that his son also suffered from breathing in carbon monoxide from the snowmobile's exhaust.
Mike sustained no internal injuries but was unavailable for comment Tuesday.
Unlike his friend, Brennise escaped Sunday's avalanche unscathed.
But that doesn't mean the snow slide didn't affect him.
"It will change the way I snowmobile, for sure," he said.
He had no intentions Tuesday to charge up another steep, snow-covered slope anytime soon.
"I may just play in the powder and the trees" from now on, Brennise said.
Bridget Manley can be reached at 875-1795 or firstname.lastname@example.org