Extensive wind slab formation has occurred. Human triggering is likely.
Wind slabs are virtually everywhere, except in the most sheltered of terrain. In certain areas these slabs will be very susceptible to human triggering.
Cornices have become more sensitive with the recent weather conditions. If triggered, a cornice failure could step down to the basal weakness.
The basal weakness persists. Forecasters are still very wary of any large features that have not yet slid this season. Very large avalanches are possible if this layer is triggered.
The strong SW winds should subside overnight, and be generally light on Tuesday morning. Then in the afternoon the SW flow will pick up strength again, returning to strong by Tuesday evening. Light precipitation is expected through Tuesday and into Wednesday, but unfortunately accumulations will only amount to about 5cm. Temperatures on Tuesday should climb to -4 by early afternoon.
A couple of recent naturally triggered wind slabs up to size 2.5 have occurred on easterly aspects in the Alpine and Treeline elevation bands.
The snowpack is settling with the recent warm weather. Moist snow was observed on sheltered solar aspects at lower elevations today. This should produce a thin crust by tomorrow morning. Due to persistent strong winds and warming temperatures, wind slabs are now widespread at all elevations and on all aspects except westerly. These slabs are of varying thickness and also have highly inconsistent results in snowpack stability tests. Forecasters continue to monitor the Dec 31 layer (surface hoar or facets) that is now buried 50cm on average. The layer has not been particularly active in avalanche activity, but it's a good thing to keep an eye on. The mid-pack is unusually strong and settled for this part of the mountain range. While, in many ways this is a good thing, it also serves to mask the significant basal weakness. There is still potential to trigger the basal layers, particularly in shallow snowpack areas, which could result in very large, destructive avalanches.
