Regions
Northwest Inland.
Winds are redistributing recent storm snow creating widespread wind slabs at upper elevations. Be wary of leeward and cross loaded slopes.
Confidence
Moderate - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
TUESDAY NIGHT: Flurries. Accumulation up to 5 m. Ridge wind strong, southwest. Temperature near -8. Freezing level 200 m.WEDNESDAY: Snow beginning in the afternoon. Accumulation 10 cm. Ridge wind moderate to strong southeast. Temperature near -5. Freezing level 500 m.THURSDAY & FRIDAY: mix of sun and cloud, light flurries. Accumulation 5-10 cm Thursday morning. Ridge wind strong, east. Temperature near -7 dropping to -12. Freezing level 400 m lowering to valley bottom.
Avalanche Summary
On Monday there was a report of a natural size 2 storm slab release on a east aspect below treeline feature that failed on facets buried by recent storm snow. Skiers also reported triggering small storm slab releases on steep convex rolls below treeline.With continued moderate to strong westerly winds it's likely that recent snow and wind loading at treeline and alpine elevations has primed conditions for human-triggering or natural avalanches.
Snowpack Summary
Light snow and strong winds continue to create wind slabs in open terrain at alpine and treeline elevations. These cover old hard wind slabs and scoured surfaces in many exposed areas. In wind-sheltered terrain, sun crusts or dry facets sit below the recent storm snow.Around 50-150 cm down, you will find a crust/surface hoar layer from mid-January, 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.Facets at the base of the snowpack could possibly be triggered from 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.