Successive moderate storms will keep danger elevated, particularly in steep, wind-affected terrain. If the 24 hour snow amounts exceed 25 cm, bump avalanche danger up by one rating.
Confidence
Moderate - Intensity of incoming weather systems is uncertain
Weather Forecast
Thursday: 10-15 cm new snow expected with freezing levels around 1000 m. Strong southwesterly winds.Friday: 10-15 cm new snow expected with freezing levels around 1000 m. Moderate southwesterly winds.Saturday: 5 cm new snow expected with freezing levels around 900 m. Moderate southwesterly winds.
Avalanche Summary
Ski cutting produced soft slab avalanches up to size 1.5 in recent storm snow at treeline and alpine elevations on Tuesday. Similar results would be expected for Thursday.
Snowpack Summary
Approximately 30-40 cm new snow now sits on top of a rain crust (or multiple crusts) that formed during the recent wet weather. Strong winds have blown snow around in exposed areas creating drifts and scoured areas. Snowpack depths are typically around 140 cm in sheltered treeline locations, although deeper (and shallower) spots certainly exist on account of the strong winds.
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.