Weak snow lies buried in the snowpack on all aspects and elevations. Cold temperatures and time have decreased the likelihood of triggering avalanches in the Tetons, however skiers and riders still have the potential to do so in steep terrain. Evaluate the snowpack if venturing onto steep slopes and pay attention to obvious signs of instability such as feeling the snowpack collapse while travelling.
At the upper elevations, soft to hard slabs could be triggered with depths to over 3 feet in steep terrain. Slabs depths of up to 2 feet are possible at the mid and low elevations. Although stability has increased since the peak loading that occurred during Thursday night’s storm, pockets of slab could still be triggered in very steep areas.
Clear skies yesterday verified that many natural avalanches occurred during the recent storm event. These slides are all thought to have taken place between sunset on Thursday and sunrise on Friday.
In the Tetons, the layer of weak snow buried on November 26th remains a concern. At that time above 8500', faceted snow was prevalent on northerly facing slopes and faceted snow mixed with crusts could be found on slopes with a southerly component of aspect . Below that elevation, the snowpack surface was faceted due to sustained cold temperatures. The storm brought approximately 40” of snow and over 4” of water to the upper elevations. Although slabs were sensitive on the 2nd, settlement, time and cold temperatures have allowed the snowpack to adjust to this new load, making the existing slabs less sensitive to triggers and therefore harder to predict.
An initial report has come in from Willow Creek in the Southwest Trails area of an avalanche that was triggered yesterday. A party of 3 was reported to have been caught. 2 of the people were buried. The 3rd was partially buried but able to extricate himself and successfully rescue the other members of his party.
