Confidence
Fair - Intensity of incoming weather systems is uncertain on Thursday
Weather Forecast
Thursday: Moderate snowfall / Moderate southwest winds with extreme gusts / Freezing level at 1800mFriday: Light snowfall / Light southwest winds with strong gusts / Freezing level at 1300mSaturday: Mainly sunny / light winds / Freezing level at 1100m
Avalanche Summary
A few size 1 human triggered wind slabs were observed on Tuesday at treeline and in the alpine. No other avalanches were reported.
Snowpack Summary
Moderate amounts of storm snow which fell Sunday have gained significant strength. Dribs and drabs of more recent snow may have been shifted into pockets of windslab by strong southwest winds. Roughly 20-45cm below the surface you may find a variety of old surfaces which formed during the early December cold snap. These surfaces include sugary faceted snow (which may overlie a crust in some areas) and spotty surface hoar in sheltered terrain. In most places the overlying slab seems to be well bonded to this interface thanks to ongoing moderate temperatures.Snowpack depths vary greatly across the region, but are significantly lower than average for this time of year. Terrain below treeline is still mostly below threshold for avalanche activity. Early season riding hazards such as rocks, stumps and logs are lurking below the surface in many areas. In glaciated terrain new snow on the surface might be just enough to hide open crevasses where supportive snow bridges have not yet developed.
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.