Avalanche Forecast
Issued: Dec 25th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
MBender,
Avalanche Canada
A buried weak layer has produced recent avalanche activity. The best approach is to continue to select conservative terrain.
Summary
Confidence
Low - Uncertainty is due to the limited number of field observations. Uncertainty is due to how quickly the snowpack will recover and gain strength.
Weather Forecast
FRIDAY NIGHT: Cloudy with isolated flurries, light south wind, alpine temperature near -8 C.
SATURDAY: Scattered flurries, accumulation 3-5 cm, light to moderate west wind, alpine temperature near -8 C.
SUNDAY: Mainly cloudy with sunny breaks, light to moderate west wind, alpine temperature near -10 C.
MONDAY: Mix of sun and cloud, light north wind, alpine temperature near -11 C.
Avalanche Summary
On Monday there was a report of a human triggered avalanche that was suspected to have run on buried surface hoar. The MIN report can be view here.
Snowpack Summary
Winds blowing from a variety of directions have redistributed new snow from last week and built slabs in lee features at upper elevations.
An active weak layer is now down 40 to 70 cm below the surface. The distribution of this layer is variable. In some areas it's surface hoar and in others it may be surface hoar on top of a crust and in others it is very hard to find if it exists at all. The bond at this interface is poor and avalanches have recently failed on this interface in the east the region.Â
Near the base of the snowpack, a crust that was buried in early November can be found. This crust likely has weak facets associated with it. There have been no recent avalanches reported on this layer, though it may be possible to trigger from shallow, rocky terrain.
Terrain and Travel
- Be careful as you transition into wind affected terrain.
- Recent wind has varied in direction so watch for wind slabs on all aspects.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
Problems
Wind Slabs
Moderate winds shifting in direction have created wind slabs in the lee of terrain features on a variety of aspects.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
A slab rests on a persistent weak layer which has the capacity to propagate avalanches across terrain features. Although the likelihood of triggering a persistent slab avalanche is reducing, the potential for triggering a high consequence avalanche should still be top of mind in your decision making process.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 26th, 2020 4:00PM
