A large avalanche triggered by skiers outside Marble on Monday was one of several recent slides that are prompting the Colorado Avalanche Information Center to urge backcountry travelers to use caution.
The Avalanche Information Center said on its website there was a “rash” of human-triggered slides statewide on Sunday after 12 to 18 inches of snow was dumped on a “garbage” snowpack in the mountains. The potential for “large, dangerous avalanches” will remain an issue for days to come, the center said.
A large slide was triggered by skiers shortly after noon Monday on what’s known as Marble Peak outside the town of Marble, according to the avalanche center’s website and the Gunnison County Sheriff’s Office.
Someone reported the avalanche to the Sheriff’s Office because they saw other skiers in the area of the slide and weren’t certain if they were trapped, according to Sheriff Rich Besecker. A sheriff’s deputy responded to the area, and an ambulance crew fromthe Carbondale Fire Department was put on standby.
The report turned out to be a “non-event” when everyone returned safely from the backcountry, Besecker said.
The two skiers who triggered the slide were skiing down the main bowl on Marble Peak, a popular backcountry skiing destination, said Blase Reardon, Aspen zone forecaster for the Colorado Avalanche Information Center. He said he couldn’t discuss the slide extensively because he hadn’t been able to discuss the event with the skiers yet.
“It’s what we would classify as a large avalanche,” Reardon said. “I think it’s a real heads-up for people.”
The “observation” page on the Avalanche Information Center’s website showed the reporting party said the slide was below tree line on an east aspect. It was a soft-slab avalanche, as are most of those occurring in Colorado’s mountains during this cycle.
The strong winds that accompanied last weekend’s storm drifted snow into extensive slabs that appear very hard and strong, the center said. The problem is the slabs are resting on “fragile” snow, it continued.
“Persistent slabs are the primary problem,” the center said in its statewide forecast. “They will remain an issue for days to come. Large, dangerous avalanches can be triggered remotely.”
“The potential for triggering large slides like the one in Marble remains our primary concern,” Reardon said. “Snow forecast for later this week may add load to these slabs and prevent them from stabilizing quickly.”
The center is currently issuing aperiodic statewide avalanche report. It will issue reports for individual zones, including Aspen, on Thursday, Reardon said.
“We’re getting enough reports from people in the backcountry to issue danger ratings,” Reardon said, “and there’s skiable snow in every zone, with people actively recreating.”
Anyone venturing into the backcountry should study conditions before they go out, he said. Several people already have triggered avalanches this fall, and some have been caught, according to Reardon. No fatalities have been reported.
“We’re well into avalanche season,” he said.
The information center’s website says there have been avalanche accidents in Colorado every month of the year. Slides are less frequent in the fall than in winter, but they are possible any time snow is on the ground, the website said.
“In the fall, it is easy to discount the amount of snow on the ground,” the center’s website said. “Grass and brush sticking out of the snow surface is misleading. You should start thinking about avalanches any time you have snow resting on a steep slope.”