Summary
Confidence
Fair - Timing of incoming weather is uncertain on Friday
Weather Forecast
Friday: Moderate to heavy snowfall starting on Friday afternoon. 10-15cm, with 20cm+ expected on western slopes. Freezing level at valley bottom for most of the day. Winds increasing to strong westerlies by afternoon.Saturday: Snow continuing, with a further 10-20cm expected (most in the southern part of the region and on western slopes). Freezing level rising briefly to around 1000m on Saturday morning. Westerly winds.Sunday: Light snow. Freezing level valley floor.
Avalanche Summary
Several natural and human-triggered avalanches have been reported over the last few days. A wind event on Tuesday triggered slabs on exposed lee slopes. On Wednesday, skiers triggered size 1.5 slabs below treeline and observed natural and cornice-triggered events up to size2, mainly on north and east aspects in the alpine. Recent avalanches have mainly been running in, or at the base of, the storm snow.
Snowpack Summary
50-80cm of recent storm snow is slowly settling into a slab over variable surfaces including a rain crust and preserved stellar snow crystals. Recent winds have caused wind slabs to develop at treeline and above, and in openings below treeline. A surface hoar layer buried in mid-December is gaining strength, but professionals are still treating it with caution, as the consequences of an avalanche on this layer would be high. Occasional hard, planar results have been reported on this layer in snowpack tests. It's now down about 130cm in the snowpack and could potentially be triggered from a shallow snowpack area or by a very heavy load, like cornice fall or group of sledders.
pgoddard,
Avalanche Canada
