Regions
Northwest Inland.
Storm slabs will build throughout the day. A CONSIDERABLE hazard may be the story in the am. Bump the hazard to HIGH in the alpine if you receive more than 25 cm of new snow by the afternoon.
Confidence
Moderate - Intensity of incoming weather systems is uncertain on Thursday
Weather Forecast
Overnight Wednesday: 5-10 cm of new snow with strong easterly winds. Freezing level valley bottom.Thursday: Snow amounts 10-25 cm with strong northeast-east winds. Freezing level valley bottom. Friday: Cloudy with isolated flurries. Ridgetop winds moderate from the East. Alpine temperatures near -8 and freezing level at valley bottom.Saturday: Mostly cloudy with some sunny periods. Ridgetop winds light/ gusting strong from the southwest. Freezing levels near 900 m.
Avalanche Summary
No recent avalanches have been reported. 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. The forecast storm snow over the next 2 days will likely have a poor bond to these older snow surfaces. 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
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.