Good skiing can be found at tree line and below. Careful evaluation of wind slabs is essential before adventuring in the alpine.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
The cold continues with a slight daytime warming. Tuesday and Wednesday are forecast for daytime highs of -15c with overnight lows of -27c. Skies should be a mix of sun and cloud with light wind from the North on both days. No snow forecast for the near future.
Avalanche Summary
One size 2 slab on an East aspect on an alpine feature on Mt. Murray.One size 2.5 slab on a NE aspect starting in the alpine in the Black Prince zone.One size 2 slab on a NE aspect starting in the alpine was observed in the Gypsum Creek zone.
Snowpack Summary
35-45cm of storm snow overlies a strong mid snowpack. This storm snow is low density at tree line and below. In the alpine, this storm snow has either turned into a wind slab or is loose and dry; it will be important to determine this before adventuring into the alpine. The buried sun crust on solar aspects down around 60cm is still a concern with this new load as well as the isolated January 17 SH also down around 60cm around 2200m. The basal facets are down 80-100cm and should still be on everyone's radar as any avalanche triggered in the upper snow pack has the potential to trigger this lower weakness.
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.
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.