Confidence
Fair - Timing, track, or intensity of incoming weather is uncertain
Weather Forecast
Wednesday: Strong S winds. Alpine temp -8. Heavy snow.Thursday: Light to moderate SE-SW winds. Alpine temp -9. Moderate to heavy snow.Friday: Light to moderate SE winds. Very light snow.
Avalanche Summary
Numerous size 1-1.5 soft slabs and loose snow avalanches were triggered naturally and by skiers on Monday. In some wind-affected areas, soft slabs were propagating widely.
Snowpack Summary
Expect new storm slabs and wind slabs to form on a widespread basis on Wednesday. A previous 40-80 cm of recent storm snow has been shifted into wind slabs on slopes lee to SE to SW winds. A couple of layers of surface hoar were buried last week in some areas. Snowpack test results on the surface hoar suggest an improving bond. The mid-pack is reported to be well settled and strong. A deeper layer of surface hoar from late November has been found intact or decomposing in some locations down a metre or more. The early November crust/facet combination near the base of the snowpack seems to be dormant. Triggering one of these persistent weak layers from a shallow snowpack area, or with a heavy trigger, remains possible.
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.