Avalanche Forecast
Regions: Banff Yoho Kootenay.
The avalanche hazard is decreasing but we still get occasional reports of larger slabs so there is a bit more uncertainty around the hazard level. The very cold temperatures are another good reason to choose terrain where you can avoid an incident.
Weather Forecast
Temperatures will rise ever so slightly on Friday with highs at treeline of between -15 to -20 C. Winds will also increase slightly with alpine winds in the Light to Moderate range out of the NE which will make it feel very cold in exposed areas so watch for frostbite!
Snowpack Summary
Previous winds from all directions have created wind slabs in lee areas of the alpine, and wind effect in many open alpine and treeline areas. In sheltered areas the surface snow is facetting quickly and beginning to sluff more easily in steep terrain. A buried thin sun crust and facet layer from Jan 27th is present on steep south aspects.
Avalanche Summary
Several smaller natural loose dry avalanches were observed in very steep terrain on Cascade and Mt Whymper in the past 24 hrs. A size 2.5 natural slab avalanche was observed on the "Sickle" on Mt Victoria on Wednesday. Some whumpfing and a few smaller slab avalanches have occurred on steep south aspects in the past week.
Confidence
Avalanche Problems
Wind Slabs
Wind slabs formed from variable alpine winds are still a concern, but are becoming more difficult to trigger with the cold temperatures. Watch for slabs over weaker facets or crusts. Several cornice failures have also been observed recently.
- Use caution in lee areas. Recent wind loading has created wind slabs.
Aspects: All aspects.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 2.5
Loose Dry
As the surface snow facets and weakens, it is starting to sluff more easily in steep terrain. Higher wind speeds will also contribute to more natural sluffing. This is mostly a problem in narrow confined terrain like gullies or couloirs.
- On steep slopes, pull over periodically or cut into a new line to manage sluffing.
- Be careful of loose dry power sluffing in steep terrain.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 1.5