Avalanche Forecast
Issued: Feb 17th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs.
TRettie,
Avalanche Canada
The likelihood of triggering the late January layer is low but not impossible. Use caution on slopes where a thick and supportive crust is absent.
Summary
Confidence
Weather Forecast
Thursday night: light flurries bringing trace amounts of snow and light to moderate northwest winds. Low of -3 at 1500m.
Friday: cloudy with light flurries bringing trace amounts of snow. Light to moderate west winds and freezing levels rising to 1300m.
Saturday: cloudy with light snow bringing up to 5cm with moderate west winds. High of -2 at 1500m.
Sunday: a mix of sun and clouds with light flurries bringing trace amounts of snow. Light northwest winds and a high of -3 at 1500m.
Avalanche Summary
On Wednesday one size one natural cornice fall was observed on a east aspect at 2200m. It was in extreme terrain and did not pull a slab on the slope below.
On Monday several small wind slab avalanches were observed in the immediate lee of ridge features. These avalanches were thin with very little destructive potential but touchy due to the surface underneath.
Snowpack Summary
Up to 10cm of new snow has buried a widespread crust and wind-affected surfaces in exposed high elevation terrain. Thin wind slabs can be found in the immediate lee of ridge features in the alpine and treeline. The new melt-freeze crust is reported to exist on all aspects and elevations except for some of the highest elevation polar aspects which may still hold dry snow. The crust is reported to be undergoing faceting in some areas.
The late-January crust/facet/surface hoar interface is buried down 30-70 cm. This layer was most reactive between 1700 m and 2000 m. While this layer now appears to be dormant in many parts of the region, recent snowpack tests suggest it is still very reactive in a few places and would still be capable of producing large avalanches if triggered.
Terrain and Travel
- Be aware of the potential for large avalanches due to the presence of buried persistent weak layers.
- When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
Problems
Persistent Slabs
The late-January weak layer is down 30-70 cm and was most reactive between 1700 and 2000 m. It is now likely dormant in many areas, especially where there is a supportive surface crust. However, recent snowpack tests suggest it is still reactive and capable of producing large avalanches if triggered. We have now entered a low probability, high consequence scenario with this layer.
Aspects: North, North East, East, West, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 18th, 2022 4:00PM
