Purcells

Recently formed wind slabs are sitting on top of buried wind slabs that are sitting on facets (weak, sugary snow). The fresh wind slabs may still be touchy and the buried wind slabs are remaining reactive to human triggers longer than is typical.

High - The weather pattern is stable

THURSDAY NIGHT: Cloudy with isolated flurries; 0-3 cm. / Light, northwesterly winds / Alpine low -16.FRIDAY: Cloudy with isolated flurries; 1-5 cm. / Light, southwesterly winds / Alpine high -15.SATURDAY: Sunny / Light, northwesterly winds / Alpine high -22.SUNDAY: Sunny / Light, northeasterly winds / Alpine high -18.

On Wednesday, numerous natural wind slab avalanches up to size 2 and several human triggered size 1-1.5s were reported on primarily southern aspects at treeline and above. Here is a link to a video of an avalanche that apparently occurred a few days ago in the Purcells. Great footage that illustrates the current wind slab problem in the region.On Saturday there was a report of a skier triggered size 2 persistent slab avalanche 30-50 cm deep on a northeast aspect in the Dogtooth range. This person was seriously injured after being swept over a 30 m cliff and carried by the avalanche for a total of 650 m. Reports of persistent slab avalanches are becoming less frequent which is creating a low likelihood, high consequence scenario in the snowpack that requires discipline and careful terrain selection to manage effectively.

Strong northeasterly ridge-top winds have created fresh wind slabs on lee features at treeline and above. Additionally, there are buried wind slabs on a variety of aspects that are sitting on facets (sugary snow) which may cause them to remain reactive to human triggers longer than what is typical for a wind slab problem.Lower down there are two layers of surface hoar (weak, feathery crystals) that were buried at the end of January and mid-January. These layers are around 30 to 80 cm deep and are most prominent at treeline and below. The surface hoar may sit on a crust on south facing slopes in specific locations which is a dangerous combination.The base of the snowpack is composed of weak and sugary faceted grains that sit on a crust. This weak layer has produced large and destructive avalanches that are sporadic in nature and very difficult to predict. See the Forecaster Blog here for more information on this problem.