With snow available for transport and increasing winds riders should anticipate slopes where wind slabs may exist by monitoring the wind direction. Use ridges and ribs to descend to a lower line that avoids a wind-loaded entry point.
Snow available for transport and increasing winds will build wind slabs directly lee of terrain features at alpine and treeline elevations. Old wind slabs from previous strong southwest winds may still be lingering in lee terrain features on northeast-facing slopes.
A layer of large, weak facets sits near the base of the snowpack. This layer is most prominent in upper treeline and lower alpine elevations. Riders are most likely to trigger an avalanche on this layer in steep, shallow terrain.
Several size 2.5 to 3 explosive-controlled wind slab avalanches were reported southwest of Tumbler Ridge.
The basal snowpack remains questionable and should still figure into terrain selection around steep features with shallow or variable snowpack areas where these layers may be more easily triggered by a person or machine as well as large wind slab or cornice releases.
Recent snowfalls have accumulated roughly 30 to 50 cm and seem to be bonding to previous surfaces. In open terrain, isolated wind slabs can be found directly lee of terrain features on all aspects in the alpine due to variable winds. Cornices have also been built at upper elevations.
The mid-pack is gaining strength and consists of rounding facets and melt-freeze crusts that are starting to degrade.
Near the base of the snowpack, a persistent weak layer composed of large and weak facets formed in November is strengthening slowly. This layer is most likely to be triggered in thin, rocky alpine and upper treeline terrain.
Tuesday night
Increasing cloud, 15 to 20 km/h west winds increasing overnight, treeline temperatures -12 °C
Wednesday
Increasing cloud, flurries starting mid-morning 2 to 5 cm new snow, 20 to 30 km/h southwest winds, treeline temperatures -6 °C.
Thursday
Cloudy with snow accumulations of 10 to 15 cm, 20 to 30 km/h southwest winds, treeline temperatures -7 °C.
Friday
Cloudy with continued flurries and 5 to 10 cm accumulations, 20 to 30 km/h southwest winds, treeline temperatures -10 °C
More details can be found in the Mountain Weather Forecast.
