Avalanche Forecast
Regions: Banff Yoho Kootenay.
Avoid terrain features that are/or have been wind loaded. Investigate snow depths as you travel through terrain and avoid committing yourself to shallow snowpack areas where the deep persistent layer could be triggered.
Weather Forecast
Expect to see anywhere from 2-10cm of new snow throughout the day on Saturday with the Western region getting the higher amount. The strong winds will gradually decrease becoming light from the SW by the evening. Temps will drop, with an alpine high of -15. Sunday into Monday will see another 10-15cm and light winds and slightly warmer temps.
Snowpack Summary
Continued snow transport and cornice growth today in the high alpine. Sun crust formation on steep solar facing terrain. Weak, facetted snow near the base of the snowpack persists in much of the range, producing isolated but large avalanches.
Avalanche Summary
No new avalanche observations or reports on Friday. On Thursday wind slabs were observed up to size 1.5 today along the Icefields Parkway in loaded pockets in the alpine.
A size 2.5 skier remote was reported Wednesday on the scramblers route of Cascade Mountain on a steep SW slope in the alpine, no involvement.
Confidence
Avalanche Problems
Wind Slabs
Consistent moderate winds, gusting to extreme from the SW have formed fresh wind slab in the alpine. Cornices have grown very large in recent weeks, so watch your exposure to them carefully.
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2.5
Deep Persistent Slabs
Several large avalanches failing naturally on the basal facet/depth hoar have been observed in the ten days. These are hard to predict, but are most likely in areas with a thin snowpack (~150cm) where the basal facets and depth hoar are prominent.
- 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: 1.5 - 3.5