Regions
Kootenay Boundary.
The wind is forecast to be strong Tuesday night into Wednesday. Plenty of new snow to redistribute into new wind slabs at tree line and alpine elevations
Confidence
Moderate - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
Wednesday: Isolated flurries / Moderate southwest wind / Alpine temperature -7Thursday: Scattered Flurries, accumulation 5cm / Moderate southwest wind / Alpine temperature -6 Friday: Flurries, accumulation 5-10cm / Light to moderate south wind / Alpine temperature -6
Avalanche Summary
Recent reports indicate avalanche activity from explosives control running on the storm snow old snow interface to size 2 at treeline and above. These are reported as both storm slab and wind slab avalanches.
Snowpack Summary
20-40 cm of new snow has buried previously formed windslabs, facets and surface hoar. Moderate to strong winds have loaded leeward features with new touchy wind slabs. A widespread crust that was buried in November is typically down 80-100cm. Recent tests show variable results with this persistent weakness. Some show results as hard and resistant and other show it may have the propensity to propagate large avalanches if triggered from thin rocky areas.
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.