Tuesday, March 5, 2013

Avalanche Fatality near Cameron Pass

The Colorado Avalanche Information Center is reporting that a backcountry skier was killed and another seriously injured in an avalanche on March 2nd. The avalanche occurred southwest of Cameron Pass, just outside Rocky Mountain National Park. The 26-year-old victim attended Colorado State University. His friend was evacuated to a nearby hospital by helicopter.

This was the 4th avalanche fatality in Colorado this season, and the 4th avalanche fatality to occur in the United States in March. On March 1st there were fatalities in Wyoming, Utah, and New Hampshire.

CAIC still warns that avalanche danger for the Front Range zone is CONSIDERABLE (Level 3), and human triggered avalanches are likely on many slopes. Today's forecast reads in part:
Observers report large whumpfs, shooting cracks, and remotely triggered avalanches. Recent avalanche activity has been on east, southeast, and west facing slopes that are near or above treeline. Today wind and storm slabs will still be easy to trigger. Slopes that are near and above treeline are the most dangerous. The winds have been both strong and from a variety of directions, so new wind drifts will be on a variety of aspects and cross-loaded terrain features.

The recent wind slabs drifted on top of persistent slabs and deep persistent slabs. The weak layers are facets in the lower snowpack or depth hoar at the bottom. These slabs have become stubborn and harder to trigger, but if you find the right spot, the result will be a large and dangerous avalanche. Avalanche mitigation work last Thursday triggered very large, destructive avalanches (R4D3) with debris piling 12 feet deep. Observers find hard and clean test results.

You can trigger one of these large avalanche by starting a smaller avalanche in the wind slabs, or by hitting a thin spot on the side or lower edge of the persistent slab. That makes it easy to move from relatively safe to very dangerous terrain with just a few steps. You should approach all avalanche terrain with a healthy dose of caution, careful evaluation, and a large margin for error.


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