Regions
South Coast Inland.
The last few days' new snow sits on a variety of potential weak sliding layers. As the storm snow settles in the coming days, it will be critical to evaluate the bond between new and old snow layers.
Confidence
Moderate - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
Wednesday: Cloudy with some sunny periods/ Moderate southwest wind / Alpine temperature -3Thursday: Flurries, accumulation 10cm / Moderate to strong southwest wind / Alpine temperature -4 Friday: Isolated flurries/ moderate north wind / Alpine temperature -5
Avalanche Summary
There are no new recent reports of avalanche activity, however I would suspect there to be continued potential for skier and rider triggering with the recent new snow, strong winds at upper elevations and a possible weak bond at the storm/old snow interface.
Snowpack Summary
30-60cm new snow overlies the previous variable snow surface from last week, which includes hard wind pressed or scoured areas, old wind slabs, weak faceted snow, or surface hoar. New wind slabs that have formed in response to southwest winds. In the Duffey Lake area, recent snowpack tests gave moderate sudden planar results down 50 cm on buried surface hoar. The widespread mid-November crust is typically down approximately 1 metre. Recent snowpack tests have shown the crust to be unreactive, but it could become a problem in shallow alpine start zones.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.
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.