Recent winds have created fresh windslabs in the alpine and isolated treeline areas. Hazard may be lower in areas where winds have not formed a slab.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
THURSDAY NIGHT - Cloudy with clear periods / light south wind / alpine low temperature near -9FRIDAY - A mix of sun and cloud / light to moderate southerly winds / alpine high temperature near -6. Some areas will experience an alpine temperature inversion.SATURDAY - A mix of sun and cloud / light southerly winds / alpine high temperature near -5, low temperature near -7SUNDAY - Cloudy with sunny periods and scattered flurries / light to moderate southerly winds / alpine high temperature near -3, low temperature near -8
Avalanche Summary
Now new avalanches have been reported in the region.
Snowpack Summary
Recent moderate winds have created windslabs in the alpine and treeline in some areas. There are two layers of surface hoar (weak feathery crystals) being reported in the top 15-30cm. The surface hoar is most prominent at treeline, but it may be found in sheltered alpine areas. Both of these layers may be associated with a sun crust on south aspects in some areas.Another notable feature in the snowpack is a combination of a crust and faceted (sugary) snow found at or near the base of the snowpack. This layer is most prominent in the alpine.The early season snowpack is highly variable in the Purcells. Total snowpack depths vary greatly throughout the region with anywhere between 70 and 150 cm in the alpine and tapering rapidly at treeline and below. In shallow snowpack areas, the bottom half of the snowpack is reportedly weak and "hollow" feeling on shady aspects due to sugary, faceted snow.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.