Aspen
AvalancheDiane Madigan · Jan 22, 2017 · Aspen
Weather
mostly clear, no wind, approx 28 degrees F
Snowpack
NE aspect of bowl, approx 10,800 to 9,200 ft elevation, 15-20" new snow
Avalanche
This group of 2 skiers skied SE aspect of bowl one at a time (from top of ridge at 11,100 down to approx 10,400), stopping below large group of trees on NE side of bowl, then one of those skiers finished the run down to flats at 9,600, awaiting 2nd skier (slopes ranged from approx 38 degree entry to 30 degree finish). Meanwhile another group of 2 skiers were above them on the NE ridge of the bowl, and proceeded to ski down the approx 30degree ridge. Before 2nd skier of 1st group began her descent, she witnessed a soft slab crack directly across from her where her ski partner's track entered slope, which then propagated uphill after a few seconds as a 2nd slab breaking at slope change, and proceeded to propagate up to the upper ridge, such that all the snow above her on the NE aspect of the bowl slid around the trees she had stopped below. Crowns were approx 20" deep (all new snow) on tops and flanks, slide paths approx 100 feet long, extending up the entire ridge to where a previous storm slab had released previous day. After snow stopped, the 2 skiers who were skiing the ridge appeared above this witness, and discussed the sequence of events. It was determined that the 2 skiers had remotely triggered the slab approx 500ft below them, that it initially broke on the original skier's track (possibly due to weakness created by that 1st ski track), then slabs released sequentially uphill as a series of soft slabs, taking approx 5 seconds for the entire ridge edge to collapse. This was confirmed by the spotter at the bottom, that the top part of the ridge released several seconds after the initial fracture at the bottom. Sorry no photos!