Avalanche Forecast
Issued: Dec 7th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Deep Persistent Slabs and Wind Slabs.
Jeff Andrews,
Natural avalanche activity has tapered off yet triggering of full depth avalanches on the basal weakness remains possible in specific tree line and alpine features. Excellent quality riding can be found in sheltered terrain!
Summary
Weather Forecast
Wednesday: Scattered flurries. Accumulation: 8 cm. Alpine temperature: Low -12 C, High -8 C. Ridge wind west: 20 km/h
Thursday: Isolated flurries. Precipitation: Trace. Alpine temperature: Low -16 C, High -13 C. Ridge wind west: 20 km/h
Friday:Â Cloudy scattered flurries: Accumulation: 4cm. Alpine temperature: Low -18 C, High -12 C
Snowpack Summary
Surface facetting and spotty surface hoar growth noted. Storm snow from last week has been stripped from exposed windward alpine features. In sheltered areas 20-30cm of settled storm snow sits atop of a supportive midpack. Our basal crust/facet/depth hoar combo near the ground remains a layer of concern. Snowpack depth 100-140cm Icefields area.
Avalanche Summary
No new avalanches observed in the Icefields area on Monday. Maligne area field team reported no new avalanches on Sunday. Although natural avalanche activity has tapered off, human triggering of large avalanches remains possible especially in features with variable thin to thick snow depths in the alpine and at treeline.
Confidence
Due to the number and quality of field observations
Problems
Deep Persistent Slabs
Natural activity is decreasing as the recent new snow stabilizes, however, triggering this layer would be a high consequence event so cautious decisions and thorough investigation is necessary.
- Avoid thin rocky or unsupported terrain features.
- Use caution on open slopes and convex rolls
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Wind Slabs
A triggered windslab has a potential to step down to deeper instabilities with a more destructive potential. Consider testing smaller slopes before committing to terrain with potential for larger propagation. Watch for hollow sounds and cracking.
- Use caution in lee areas. Recent wind loading have created wind slabs.
- Use conservative route selection, choose moderate angled and supported terrain with low consequence.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 8th, 2021 4:00PM
