Regions
Banff Yoho Kootenay.
The new snow has helped to improve the ski quality. More snow for Wednesday will add load to the existing weaknesses and we may start to see more avalanche activity before things cool off and snow subsides.
Weather Forecast
Tuesday's storm will taper off tonight, snowfall totals will be 10-25 cm. A smaller system starting around noon on Wednesday will bring 10-15 cm. FL will drop tonight and through Wednesday as the front passes. Winds will also drop to light with some strong gusts from the W-SW. No snow forecasted for the remainder of the week.
Snowpack Summary
The Dec 3rd interface is buried by 30-50 cm of snow and is a layer to watch right now. It consists of facets and large surface hoar below 2000m, wind effect in the alpine, and suncrusts on S & SW aspects. Moderate S & SW winds are building soft slabs in the lee of alpine features. The lower snowpack is well settled where the depth is close to 1 m.
Avalanche Summary
Small windslabs local to ridgecrests are reactive to skier traffic in the alpine and at treeline. Some cracking observed in a steep below treeline glade today where the Dec. 3rd surface hoar was present. Again, limited observations in the alpine due to poor visibility.
Confidence
Track of incoming weather systems is uncertain
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.
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.