While the Avalanche Danger level has improved, skier-triggered avalanches are still possible in terrain where wind slabs are present. Lots of early season hazards out there, as the snowpack is still shallow and weak.
Confidence
Good - Due to the number and quality of field observations
Weather Forecast
A mix of sun and cloud expected Thursday with temperatures near -3 degrees. Winds will be from the West at 40km/h gusting to 70km/h. No precipitation is expected Thursday, but light flurries are possible on Friday.
Avalanche Summary
Nothing new.
Snowpack Summary
Surface faceting and surface hoar growth to 10mm in sheltered areas below 2200m. Variable wind effect in specific terrain features in the Alpine, such as lee and cross-loaded features and gullies. Test profile at 2300m on SE asp. Basal crust layer (from late Oct) is up to 20cm thick. Moderate to hard compression tests resulted on this crust. Midpack is primarily 1F density.
Problems
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.
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.