Travel and ski conditions have improved! Watch for small wind slabs, and continue to use caution at higher elevations, particularly where the snowpack is thin and triggering the deeper persistent weak layers remains a possibility.
Winds from a variety of directions have formed small isolated wind slabs on multiple aspects in alpine lee areas over the Feb 3 interface. In some places, these can be triggered by humans. Use caution near ridgecrests and when entering steep, confined terrain.
Several persistent weak facet layers exist in the mid-pack and at the bottom of the snowpack. Sporadic avalanche activity continues on these layers and the theme seems to be rocky, steep, thin snowpack areas in the alpine. Triggering these deeper layers can result in large avalanches.
Some natural loose wet avalanches on steep solar aspects occurred Saturday with daytime heating.
Skiers triggered a size 2.5 slab on a S aspect at 3050 m on Mt Vaux on Thursday while boot-packing.
A size 2 and 2.5 skier-triggered deep persistent slab at 2750 m on a SE aspect in the Cirque Forepeak area occurred Tuesday.
The deeper layers can still be triggered in thin snowpack areas at high elevations.
Suncrust on steep solar aspects. Isolated wind slabs in the alpine. 10-25 cm of facetted snow over the Feb 3 crust. The crust is found in most locations except above 2500 m on N aspects, and varies in thickness from 0.5-15 cm with a thicker crust in deeper snowpack areas and at lower elevations. Persistent weak facet layers remain present in the mid and bottom of the snowpack and have recently produced avalanches on the ground in rocky thin snowpack areas at higher elevations.
A ridge of high pressure starts to break down on Sunday as clouds move into the region during the day. Ridgetop winds will stay in the light to moderate range out of the west. No significant new snow is expected though isolated flurries may occur. Treeline temperatures will range from -10°C to -4°C.
