Avalanche Forecast
Issued: Dec 8th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
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Avalanche Canada
Areas with thicker pillows of wind-drifted snow are the primary concern as they're covering a hard, smooth, slippery crust. Be cautions near ridges, ribs, and cross-loaded gulleys.
Summary
Confidence
Moderate - Uncertainty is due to limitations in the field data.
Weather Forecast
Thursday and Friday should be quiet with the next storm arriving Friday overnight.
OVERNIGHT: Trace of snow, temperatures around -5 to -10 C, moderate to strong west wind.
THURSDAY: Trace to a few centimetres of snow. Continued cold with temps around -10 C. Light to moderate westerly wind.
FRIDAY: Flurries up to 5 cm. Moderate southwest wind. Treeline high temperatures around -10 C. The next storm arriving late in the day ....
SATURDAY: Sunrise should show 10 - 20 cm of new snow which should double in depth by sunset. Moderate to strong southwest winds. Warmer temperatures with freezing level rising to around 1500m.
Avalanche Summary
We have no new avalanche observations from this region; quite possibly due to travel restrictions. If you are out in places like the Hurley and see avalanches please drop a MIN.
Snowpack Summary
Upper snowpack: 10-20 cm of recent snow is covering wind affected surfaces including the Dec01 crust.
The south, having endured warmer temperatures and more rainfall, is largely below threshold for avalanches at most elevations. Previous snow has seen extensive wind effect, exposing the rain crust clean in some areas, while piling up to 40 cm over it in others.
In the north, the new snow may be sitting over a layer of surface hoar crystals, older wind affected snow in the alpine, a thick crust below 1800 m or a combination of these.
A couple of buried weak layers produced large avalanches during a previous storm. If these layers remain active they'll be confined to alpine elevations.These include a layer of surface hoar down an estimated 90-120 cm and deeper crust/facet combo layer.
Average snowpack depths in the alpine are 150-200 cm. Below treeline, depths of 30-50 cm around 500 m.
Terrain and Travel
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Make observations and assess conditions continually as you travel.
- Closely monitor how the new snow is bonding to the old surface.
- Keep in mind the crust offers an excellent bed surface for avalanches.
Problems
Wind Slabs
Recent snow and wind have built isolated slabs in wind-exposed areas which may be reactive to human triggering, especially where the snow is not well bonded to a buried crust.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
This problem may exist in the north of the region. We have few observations and plenty of uncertainty around whether a buried weak layer remains a problem at upper elevations.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Dec 9th, 2021 4:00PM
