Regions
Northwest Inland.
Be alert for lingering wind slabs at higher elevations.
Confidence
Moderate - Timing, track, or intensity of incoming weather system is uncertain on Thursday
Weather Forecast
Wednesday: Cloudy with new snow up to 5 cm. Alpine temperatures near -3 and freezing levels 900 m. Ridgetop winds moderate from the East. Thursday: Snow amounts 10-20 cm, accompanied by strong ridgetop winds from the East. Freezing levels near 800 m.Friday: Cloudy with isolated flurries. Alpine high of -7 and freezing levels near 700 m. Light winds from the East.
Avalanche Summary
No recent avalanches have been reported. Over the past weekend, wet loose avalanches to size 2.5 were reported at all elevations on sunny aspects. Some of these stepped down to basal facets in northern parts of the region. In the south of the region, cornice failures on north facing ridge lines in the alpine were also reported, to size 2, but not triggering slabs below. With forecast snow and wind you can expect the avalanche hazard to rise.
Snowpack Summary
Variable snow surfaces exist including dry snow, surface hoar, crusts and moist snow at lower elevations. High elevation, north aspects may have lingering wind slabs in immediate lee features which sit on surface hoar and/ or a sugary facet layer found down 10-30 cm.A surface hoar and crust layer from January is buried around 80 to 140 cm in the southwest of the region. This layer still has the potential to be triggered from a thin snowpack spot, or with a large trigger like a cornice fall.Sugary facets exist at the bottom of the snowpack in steep, rocky, and shallow snowpack 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.