Fresh wind slabs are expected to elevate danger at higher elevations on Monday.
Confidence
Moderate - Intensity of incoming weather systems is uncertain
Weather Forecast
Wind, with a little bit of snow, in the forecast.SUNDAY: Cloudy with light snow, accumulations between 5 and 10 cm. Strong southwest or west winds with freezing level near 1000 metres.MONDAY: Mix of sun and clouds with isolated light flurries possible, freezing levels returning to valley bottoms and light to moderate westerly winds.TUESDAY: Thin cloud, colder, drier, and a light northerly wind.
Avalanche Summary
Avalanche activity reports have greatly diminished. Beside relatively harmless sluffs, there was a single report of a rider-triggered size 2 avalanche 40 cm deep, on a south aspect. It released on the mid-January surface hoar / facet layer.
Snowpack Summary
Twenty to 50 cm of previous snow is settling over the previous mid-January snow surface which includes buried surface hoar in sheltered areas, crust on south aspects and/or widespread facets. This slab is particularly touchy where where the buried surface hoar is preserved. Strong southwest winds during that storm created wind slabs in leeward terrain features. Another surface hoar/facet persistent weakness from mid-December may be found down 70-120 cm and is generally considered dormant. However, we are still receiving occasional reports of sudden results in snowpack tests, suggesting that it has to potential to propagate into a large avalanche if triggered; watch shallow snowpack areas where the layer is closer to the snow surface. Fresh new wind slabs are likely to develop below ridge-tops on Sunday when the next front passes through.
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.