Avalanche Forecast
Regions: Banff, Banff Yoho Kootenay, East Side 93N, Field, Kootenay, LLSA, Lake Louise, Little Yoho, Sunshine, West Side 93N.
The extreme cold temperatures will continue for a few more days. The snowpack is weak and although natural activity has slowed, human triggering remains possible in all steep, skiable terrain. In some areas below treeline, the entire snowpack sluffs away underfoot and is unskiable.
Confidence
High
Avalanche Summary
Outflow (east) winds did some wind loading near Field as the cold air moved in and several small windslabs were reported on Mt. Stephen above the CPR tracks. These were small, but they ran a long way due to the facets.
Snowpack Summary
The snowpack is shallow and weak with a base of facets that won't support much weight. A 20-60 cm slab overlies this weak base and could easily be triggered in some locations. Loose, faceted sluffs are being triggered below treeline in some locations and any avalanches that do release will run further than expected with the cohesionless snow.
Weather Summary
The bitter cold Arctic ridge of high pressure will continue to dominate the weather for the next few days. Sunshine recorded -41 at their study plot today. Expect the same until Thursday, when the flow shifts back to SW and temps will rise back to more normal values.
Terrain and Travel Advice
- Uncertainty is best managed through conservative terrain choices at this time.
Avalanche Problems
Deep Persistent Slabs
A 20-60 cm slab overlies the weak basal facets which continue to get weaker each day. No recent natural avalanches have been observed, but we expect human triggering to remain possible on large slopes. This problem will be around for a while.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2.5