Avalanche Forecast
Issued: Dec 15th, 2024 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
Parks Canada,
Avalanche Canada
New snow and strong SW wind has created wind slabs on all aspects in the alpine. Wind slabs can also be found in lee terrain at tree line.
Ski quality is excellent in terrain that is sheltered from the wind.
Summary
Confidence
Moderate
Avalanche Summary
Several avalanches ranging from size 1-3 observed in the highway corridor on a road patrol today.
These were likely initiated by wind loading on Saturday and Sunday evening.
Snowpack Summary
~20cm of recent storm snow combined with moderate to strong Southwest wind has created wind slabs.
A persistent weak layer remains down 50-70cmcm. This interface consists of surface hoar in sheltered locations, a sun crust on solar aspects, and continues to produce moderate-hard sudden results in test profiles.
The base of the snowpack is comprised of several dense, melt-freeze rain crusts formed in October/early November.
Weather Summary
Weakening low pressure system early this week before a significant storm arrives on Wed.
Tonight Trace precipitation. Wind SW 15km/h
Mon Mainly cloudy with isolated flurries. Trace precipitation. Alpine high -9 °C. Ridge wind SE 10. Freezing level (FZL) 700m.
Tues Cloudy with sunny periods & isolated flurries. Trace precipitation. Wind SW 15. FZL 900m.
Wed Snow! ~24 cm. Alpine high -3. Wind SW 25-45. FZL 1500m
Terrain and Travel Advice
- Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
Problems
Wind Slabs
Recent snowfall has been redistributed by strong S-SW winds building widespread wind slab in the Alpine. At tree line elevation, wind slab can be found in leeward terrain. If triggered, wind slabs may step down to a persistent weak layer buried 60-80cm deep.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
60-80cm of snow overlays a layer of surface hoar in sheltered zones, and a sun crust on steep, solar aspects. Activity on this layer had slowed in recent days, but the new load from this current storm could re-awaken this problem.
A Rutschblock 3 was recorded at 2050m in the Asulkan area on Sat down 65cm
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 16th, 2024 4:00PM
