The avalanche season is not over yet.
A pair of skiers triggered a domino effect from an avalanche on Tuesday at Bald Mountain east of Breckenridge, estimated to be half a mile wide and up to 10 feet deep, Colorado Avalanche Information Center officials said.
A wind-blown snow avalanche destabilized two lower layers of snow, one after the other, causing a major avalanche. No one was caught or injured by this.
According to the Colorado Avalanche Information Center report, the first skier triggered a 50-foot-wide wind slab. The skier escaped to a pre-determined safety zone. The wind slab, in turn, triggered another slab 3 to 4 feet deep below.
As these slabs approached the bottom of the chute, the entire left side of the chute shattered, sending a third slab of snow sliding down.
The two skiers estimated that the fallen slabs measured up to 10 feet in some places based on the crown left behind, which stretched nearly half a mile.
The race was the second of the day for the skiers on Bald Mountain. They previously skied a more easterly face.
“We grossly underestimated the potential for deep slab avalanches today,” the skiers wrote in the Colorado Avalanche Information Center report. “Our biggest takeaway is that this snowpack is far from stable in many more places than you might expect.”
Ethan Greene, director of the Colorado Avalanche Information Center, called the event “rare”.
The lower two layers of snowpack were mostly stable, Greene said. The Colorado Avalanche Information Center saw little activity in them in the area and considered them dormant, making the avalanche somewhat unusual.
Anna DeBattiste of the Summit County Rescue Group said the two skiers reported the avalanche immediately after it started, providing colorful words in their description.
Expletives aside, DeBattiste wants to encourage people to report any avalanches they witness, as this can relieve the response teams, many of which are all-volunteer groups.
Last weekend’s storms brought a foot of snow to the Breckenridge area. According to the Colorado Avalanche Information Center report, high winds moving south and west carried snow up the ridges and deposited snow on the north, northeast and east facing slopes.
Such winds will scour ridges, create cornices and deposit pillows of snow along the slopes. Greene and the Colorado Avalanche Information Center encourage backcountry travelers to avoid wind-loaded features like ledges and pillows.
Likewise, Greene encourages anyone heading into avalanche territory to do so early in the day this time of year.
“The adage is: start early, finish early,” he said.
With the warm days and cold nights of spring, it’s safest to venture out in the morning. The snow will soften as the sun and temperatures rise, and the avalanche risk will increase as the day progresses. This soft snow will freeze again overnight, sticking the snowpack and tending to stay firm all morning, officials said.
Although Summit County’s avalanche danger was rated as low Friday night, officials say that doesn’t mean avalanches are impossible. Local forecasts indicate that the highest avalanche hazard will be on northeast, north and northwest facing slopes near and above the treeline.
A storm is expected to hit the Rocky Mountains this weekend and drop up to 8 inches at high elevations. Strong northwest winds are expected to accompany the snow, drifting into slabs that could crack and break under or above skiers, the avalanche center reports.
Any avalanches that occur are expected to be “large” to “very large,” according to avalanche officials, much like the Bald Mountain landslide this week.
So far in the 2021-22 season, the Colorado Avalanche Information Center has reported nearly 5,000 avalanches. Greene considered that to be normal, although he clarified that not all avalanches are reported.
Deaths are the only exact count recorded by the center. There have been six avalanche fatalities this season, compared to 12 last year. Colorado’s 10-year average is six per season.
Witnesses can report an avalanche by calling non-emergency dispatch at 970-668-8600.
Backcountry Travelers Can Check Out Colorado Avalanche Forecasts in line at Avalanche.state.co.us/forecasts.