Avalanche Forecast
Regions: Banff Yoho Kootenay.
Strong to Extreme alpine winds will continue to develop the wind slab problem at upper elevations. Limit your exposure to overhead hazards like cornices.
Weather Forecast
Light snow overnight Monday with accumulation amounts of 2-5cm. Alpine winds will continue to be in the strong to extreme range over the next few days. Another more significant pulse of snow is forecasted for Tuesday night with forecasted accumulation amount of 10-20cm. Freezing levels will remain near valley bottom.
Snowpack Summary
Strong to Extreme SW winds forming new wind slab in the alpine down to tree line. Watch for buried sun crust on steep solar aspects. The Feb 1 rain crust is down 30-60 cm and present below 1900 m. In thin snow pack areas a dense mid-pack sits over a weak, faceted base. Thick snowpack areas have a denser base with few weaknesses.
Avalanche Summary
Direct observations of a few small natural avalanches initiated from strong SW winds were noted Monday afternoon.
Confidence
Avalanche Problems
Wind Slabs
New wind slab development in the alpine and exposed areas at tree line. Expect this problem to be reactive to human triggering where new loading exist.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
- Be careful with wind loaded pockets while approaching and climbing ice routes.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2
Deep Persistent Slabs
Avalanche activity on the basal facets has slowed down but the weakness in the snowpack remains a concern. These are hard to predict, but are most likely in areas with a thin snowpack (<130cm) where the basal facets and depth hoar are prominent.
- Use caution in thin snowpack areas.
- Pay attention to overhead hazards like cornices which could easily trigger the deep persistent slab.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Unlikely - Possible
Expected Size: 2 - 3.5