Avoid avalanche terrain at and above treeline. Skiers report triggering a size 2.5 avalanche in the Maligne area on Thursday.
Weather Forecast
Snowfall is expected to tapper off over the next 2 days. 5-10cm over the next 24hrs with the potential for more in the Icefields area. Cold arctic area is invading the valleys to the North and East. To the South, in the Icefeilds area, and at upper elevations warming moist air is giving inversion conditions. The colder air will prevail by Saturday.
Snowpack Summary
Soft to hard slabs are forming in the alpine under the influence of moderate to strong Westerly winds. In the Columbia Icefields area 70cm of new snow has fallen in the past 48 hours, 40cm of which fell in the past 24hrs. At treeline soft slabs exist in the most wind exposed terrain. Lesser amounts of snow fell near Jasper townsite.
Avalanche Summary
Poor visibility and flat light has obscured observations at treeline and above. The large snowfall amounts in the past 48 hrs and field tests in the alpine and treeline lead us to believe that avalanche activity is underway at upper elevations, both as point release and slabs. Cold temps in the north have stopped moist avalanche below treeline.
Confidence
Wind effect is extremely variable on Friday
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.
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.