Avalanche Forecast
Issued: Dec 18th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
isnowsell,
Avalanche Canada
This is not your typical coastal mountain snowpack - it is generally facetted, weak and shallow, with a significant weakness at the bottom of the snowpack. Assess for stiff, cohesive, wind slabs on the surface, that if triggered have the potential to step down to deeper weak layers.
Summary
Confidence
Moderate
Avalanche Summary
No new avalanche activity has been reported over the last few days.
If you head out into the mountains, please share your photos or observations on the Mountain Information Network. Your information helps us understand local conditions!
Snowpack Summary
Recent storm snow continues to facet with current cold temperatures. These sugary crystals will be easily redistributed by the current cold, Northerly winds into drifts and stiff wind slabs.
In general, the snowpack is weak, facetted, and shallow for mid-December. Snowpack depths generally range from 80-120cm at treeline. Widespread large basal facets and even depth hoar have been reported. At the moment much of the snowpack lacks much cohesion for this weak basal snow to be an issue. However, as the upper snowpack gains cohesion, with time and more snow, this deep persistent layer will likely become more of a concern.
Weather Summary
Cold arctic air dominates the weather throughout BC this week. High uncertainty remains over the potential of snowfall starting Tuesday.
Sunday night
Clear. No precipitation. Temperatures around -25 to -30 C and generally light Northeast winds in the alpine.
Monday
A mix of sun and cloud, with no precipitation. Temperatures -20 to -25 C and light Northeast winds in the alpine.
Tuesday
A mix of sun and cloud, with no precipitation. Temperatures -20 to -25 C and light North winds in the alpine.
Wednesday
A mix of sun and cloud, with no precipitation. Temperatures -20 to -25 C and light Northeast winds.
TuesdayMore details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
- Conditions may have improved, but be mindful that deep instabilities are still present.
Problems
Wind Slabs
Cold, Northerly winds are redistributing the recent snow into potentially reactive windslabs. With cold temperatures windslabs will likely take longer then usual to stabilize and bond to the underlaying surfaces.
Remember that small wind slabs on the surface could scrub down to deeper weak layers in the snowpack, resulting in much bigger then expected avalanches.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Weak crystals sit at the base the snowpack creating concern for large avalanches. Primarily a concern in areas were a cohesive upper snow pack exists (like wind affected slopes) and even a small avalanche could scrub down to the weak layer.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 19th, 2022 4:00PM
