Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches possible, human triggered probable.
Alpine
Natural and human triggered avalanches likely.
Treeline
Natural and human triggered avalanches likely.
Below Treeline
Natural avalanches possible, human triggered probable.
Alpine
Natural and human triggered avalanches likely.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Regions
Northwest Coastal.
New snow and wind are driving a natural avalanche cycle.
Confidence
Moderate - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
MONDAY: Clear in the morning, with cloud and snow developing by afternoon. 20-30 cm overnight. Freezing level near 500 m. Strong south-westerly winds.TUESDAY: Around 10 cm snow. Freezing level near 400 m. Strong westerly winds.WEDNESDAY: 5-10 cm snow. Freezing level near 400 m. Strong westerly winds.More details can be found in the Mountain Weather Forecast.
Avalanche Summary
Poor weather has kept avalanche observations to a minimum, but initial reports of a natural cycle up to size 3 came in on Sunday. Ongoing avalanche activity is expected as stormy conditions continue.
Snowpack Summary
Recent storm snow accumulations of 40-80 cm have been affected by ongoing moderate to strong winds from the south-west through north-west at alpine and treeline elevations. This new snow has buried old hard wind slabs, scoured surfaces and sastrugi in many exposed areas. In wind-sheltered terrain, sun crusts or dry facets sit below the recent storm snow.In the upper pack is an interface of sun crusts, facets and spotty surface hoar (which is most prevalent in sheltered treed locations). Deeper in the snowpack, around 50-150 cm down, you'll find a crust/surface hoar layer, which still has the chance to surprise you and could be triggered from a thin snowpack spot, or with a large trigger like cornice fall. Basal facets may be found near the bottom of the snowpack.
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.