Natural avalanches possible, human triggered probable.
Alpine
Natural and human triggered avalanches likely.
Treeline
Natural and human triggered avalanches likely.
Below Treeline
Natural and human triggered avalanches likely.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches possible, human triggered probable.
Regions
Banff Yoho Kootenay.
http://www.pc.gc.ca/apps/scond/Cond_E.asp?oID=15678&oPark=100092Good time to avoid all avalanche terrain and stay in bounds. We are seeing many unusual & large avalanches. Their have been several avalanche involvements over the week. The forecasted sun and warm temperatures will likely trigger more avalanches.
Weather Forecast
Clear skies forecasted for the next few days, light winds, and alpine temperatures expected to climb to +3C on Saturday. Sunday will be cooler as a cold front passes in the morning. The warming and direct sun will likely trigger more large natural avalanches on Friday and Saturday.
Snowpack Summary
Strong winds have created widespread windslabs on lee aspects (N-SE) and stripped all the snow off windward aspects. The new snow and wind loading has overloaded the basal weakness and is responsible for the widespread natural avalanche cycle we have been seeing. Conditions remain prime for human triggering
Avalanche Summary
Avalanche control today on Bourgeau and Vermillion produced several large avalanches up to size 3.5. Impressive propagations up to 500 m and crowns as deep as 2 m. Some avalanches today and yesterday triggered large sympathetic avalanches on neighboring terrain and on the backside of features being controlled. Touchy!
Confidence
Due to the quality of field observations
Problems
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.