Strong winds and new snow have created wind slabs in the Alpine and above-treeline terrain. In the Alpine, a human is likely to trigger an avalanche (Considerable) and in the Treeline terrain, this is possible (Moderate). Isolated pockets of complex terrain and steep leeward slopes will have the most unstable snow, choose your terrain carefully with this wind slab problem in mind.
12" of new snow fell at Leavitt Lake Wednesday night into Thursday morning. Swirling winds and a strong Southwest flow created fresh wind slabs in the Alpine and above Treeline on Thursday. Pay attention to terrain features in exposed areas as these slabs will need time to stabilize. The leeward side of ridges and convexities in steep terrain will remain suspect.
We toured in the Leavitt Lake area. Above us, we had party cloudy skies with a few sun breaks. The wind was present throughout the day with strong gusts on ridges and in the Alpine. Obvious signs of wind pressed snow was evident in the terrain with ribbons in the snow and cornices on ridges. In the area we dug, the snow was on average 200 cm's deep. 12" + of new snow and heavy drifts were present in the terrain and in sheltered areas in the trees. We dug in the snow above 10K and found fist harness snow on top and 1 finger snow through the pack down 100cm's (we did not dig to the bottom). We felt the effect of wind slab on all aspects.
