Regions
Kootenay Boundary.
Heavy snowfall and wind has resulted in HIGH avalanche danger at higher elevations.
Confidence
Moderate - Forecast snowfall amounts are uncertain
Weather Forecast
FRIDAY: Still snowing with 10 to 20cm forecast by Friday evening with strong SW winds. Continued warm with freezing level unchanged (around 1300m).SATURDAY: Scattered flurries with light snowfall, moderate southwesterly winds and freezing levels around 1000 m.SUNDAY: Flurries bringing another 5-10cm with moderate southerly winds and freezing levels dropping to 500m.
Avalanche Summary
Reports from Wednesday include numerous natural and skier and explosives controlled storm and wind slab avalanches up to Size 2. Slab avalanche size and likelihood is expected to increase with forecast new snow, wind, and warming.
Snowpack Summary
30-60cm in the past few days brings the total to 50-100cm since the weekend, which is bonding poorly to a sun crust on previously sun-exposed slopes, or facets and large surface hoar shaded aspects. Wind slabs have formed in exposed areas from shifting SW to NW winds and more snow and wind is forecast. A variety crusts and thin surface hoar layers, in the upper snowpack are becoming more of a concern with this increased load. Areas with a shallow snowpack (less than around 170 cm) generally have a weak snowpack structure with a deep persistent weakness of facets near the ground.
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.