Regions
Kootenay Boundary.
Confidence
Fair - Intensity of incoming weather is uncertain on Monday
Weather Forecast
Saturday: Light snowfall with the freezing level at valley bottom. Moderate-strong westerly winds.Sunday/Monday: Weak disturbances could bring further light snowfall. Expect freezing levels to hover between 1100m and valley bottom. Strong south-westerly winds.
Avalanche Summary
Recent reports include isolated human triggered Size 1 thin soft wind slab avalanches running on large surface hoar, on south through east facing treeline slopes.
Snowpack Summary
Recently developed surface hoar and near-surface facets are likely to get gently buried by light snowfall over the next few days, potentially creating a weak interface which could become reactive with enough new load from snow and/or wind-transport.In the meantime, the snowpack is relatively well bonded, except for buried surface hoar layers in the upper 15cm (with sudden test results on these layers in some locations) and soft and hard wind-slabs on certain slopes in the alpine and around treeline. Facets at the base of the snowpack could create a deep persistent slab problem that deserves attention in shallow snowpack areas on planar rocky slopes.
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.