The deeper weak layers are active and human-triggered avalanches are likely. A special avalanche warning has been issued which includes our region.
Be extra cautious in wind affected areas where a stiffer slab can propagate widely.
Recent storm snow and strong winds have formed a reactive slab over the December 17th facet layer. This problem is most significant at tree line and in the alpine where the snow is heavily wind affected, but it does exist in some areas below tree line. If triggered these slabs could also step down and initiate a deep persistent slab on the basal facets.
The bottom of the snow pack is inherently weak with well developed Facets and Depth Hoar.
Avalanche Control along the Icefields Parkway on Thursday produced several large slab avalanches in wind loaded tree line slopes. These slides were triggered as winds slabs and stepped down to ground with wide propagation. Below tree line slopes produced small slab avalanches running at the storm snow interface.
Numerous natural avalanches up to size 2.5 were also observed in the alpine along the Icefields Parkway.
20-30 cm of recent storm snow has developed into a slab over the December 17th facets. Alpine and tree line slopes are heavily wind affected. Facets and depth hoar make a weak base in most areas. Snow height ranges from 50-120cm.
Overnight Thursday and through the day Friday, the forecast calls for mainly cloudy skies, light flurries, and moderate winds from the southwest. Temperatures steady around -10.
