Regions
Kootenay Boundary.
Forecast snowfall amounts vary widely in the region. Lean toward the Considerable rating if you're seeing more than 20cm of new snow around you - or above you.
Confidence
Moderate - Intensity of incoming weather systems is uncertain
Weather Forecast
Tuesday: Flurries overnight Monday are expected to deliver 5-10cm of new snow to the region by Tuesday morning. Continued flurries on Tuesday will bring an additional 5-10cm of new snow. Winds will be moderate gusting to strong from the southwest. Freezing level at 800 metres with alpine temperatures around -7.Wednesday: Isolated flurries will bring a trace of new snow. Winds light to moderate from the west. Freezing levels dropping to valley bottom with alpine temperatures to -9.Thursday: A second storm wave will deliver 10-15cm of new snow. Winds light gusting to strong from the southwest. Freezing levels near valley bottom with alpine temperatures to -8.
Avalanche Summary
Explosives control in the north and south of the region on Saturday produced several size 1-2 avalanches with crown depths up to 15cm. Most size 1 results were running as loose dry avalanches and all results were releasing above the December 18 storm snow interface . Friday's observations included a natural size 1 avalanche in steep northwest-facing alpine terrain.
Snowpack Summary
Under 5cm of new snow fell overnight in the region. This has buried wind scoured surfaces in exposed areas and possible 2-5mm surface hoar in sheltered areas. Below this, 10-15cm of new snow over Thursday and Friday may lie above a sun crust on solar aspects in some parts of the region. Where it exists and has been tested, this interface has produced easy sudden collapse results. The new snow brought storm snow totals to 30-60cm since snowfall began at the beginning of last week and loaded leeward features with wind slabs under moderate to strong winds. The storm snow buried old wind slabs, facets and surface hoar. The interface at this layer continues to produce easy to moderate results in snowpack tests. A widespread crust that was buried in November is now 80-100cm deep in the snowpack. Recent tests show variable results with this persistent weakness. Some show results as hard and resistant and others show a sudden character, suggesting it may be likely to propagate if triggered from thin, rocky areas.
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.