New wind slabs may exist in leeward terrain features around ridge crests. Continually assess local conditions as you travel and use extra caution as you transition into wind affected terrain.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
Unsettled conditions are expected on Wednesday morning as the current storm system exits the region. Light flurries may linger through the morning with sunny breaks are possible in the afternoon. Freezing levels are forecast to reach 1200-1500m and alpine winds are expected to be moderate from the south easing to light from the north by the afternoon. High pressure should be the dominant feature for Thursday and Friday. Dry and sunny conditions are expected both days with freezing levels below 1000m and light alpine winds from the north.
Avalanche Summary
No new avalanches have been reported since the weekend. On Saturday, a natural cornice fall on Decker Mountain in the Spearhead Range triggered a size 1.5 wind slab on a northwest facing alpine feature. Looking forward, new wind slab activity is expected in higher elevation lee terrain over the next couple days but these wind slabs are generally expected to be small and thin.
Snowpack Summary
5-15cm of new snow overlies a medley of old surfaces which includes a melt-freeze crust on solar aspects in the alpine, stubborn wind slabs in exposed higher elevation terrain, and well-developed surface hoar in sheltered areas. Moderate southerly winds are redistributing these new accumulations into soft wind slabs in high-elevation lee terrain. The mid and lower snowpack are generally strong and well-settled.
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.