Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Regions
Jasper.
Human triggering remains a possibility. A strong, thick supportive mid-pack over the basal weakness is critical to safe travel, especially in shallow snowpack regions. Ice climbers should be wary of loose dry avalanches in gulleys.
Weather Forecast
Saturday will be cloudy, no precipitation, alpine temperatures high -20 C, and light East Ridge winds. Sunday will be sunny with cloudy periods, no precipitation, alpine temperature low -23 C and high -14 C with light ridge winds.A detailed mountain weather forecast is available from Avalanche Canada.
Snowpack Summary
50cm from Feb 2nd was followed by strong Northerly winds and cold temperatures. This snow overlies a dormant but persistent weaknesses of surface hoar, crusts, and/or facets. Cold temps have weakened the structure of the slab over this layer and it lays dormant, for now. A deep persistent basal facet/depth hoar weakness exists in shallow areas.
Avalanche Summary
On Feb 7th, 3 people were involved in a sz 2 in the Surprise Valley area of Maligne. This area is typically shallow and facetted with a weaker mid-pack. Slide was triggered in the basal weakness while traveling through the trees on a W aspect, 1950m, on a 30° slope. One member was fully buried and located and recovered by their partners.
Confidence
Problems
Loose Dry
Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.
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.