Great skiing in Jasper right now. The Dec 3 interface down 60cm has not been reactive with this new snow, however we believe it is still touchy in isolated terrain features between 1700 - 2000m. Carefully evaluate open slopes in the trees.
Weather Forecast
Snowfall amounts are tapering off, but a series of scattered flurries is expected to bring an additional 5cm by Saturday. Temperatures remaining cool, with daytime highs near -5C. Freezing level to remain below 1500m. Winds light and variable through to the weekend.
Snowpack Summary
70 cm of snow in the past week is settling rapidly and appears to be bonding well. The main concern is where this snow sits on the Dec3 surface hoar, most likely between 1700-2000m on sheltered North aspects. A touchy 15cm windslab can be found in lee areas at treeline. The midpack is supportive above 1700m and there is a new raincrust below 1200m.
Avalanche Summary
Numerous natural slab avalanches in the alpine up to size 3 were observed in the Columbia Icefield area as well as the lands adjacent to Marmot Basin. Several of these slides started as a storm slab, which stepped down to trigger basal weaknesses and caused large full depth avalanches. Loose dry point release were noted out of steep rocky terrain.
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.