Avalanche control work is planned along Highway 93 on Thursday, January 9th from 12:00pm to 4:30pm. Travelers on Highway 93 north can expect delays of one to two hours at a time between Parker Ridge and just north of Saskatchewan Crossing.
Weather Forecast
A moist southwesterly air flow will bring snow flurries and warming temperatures into the weekend with daytime highs on thursday and friday of +2 in the townsite area. In the Columbia Icefields area, winds are expected to pickup into the weekend along with snowfall amounts.
Snowpack Summary
Last weekend's storm snow overlies older wind slabs. In the alpine this newer snow has itself be blown into storm slabs which shear with easy to moderate force. The base of the snowpack is weak and unstable at all elevations. Near treeline the midpack is supportive and untracked powder can be found in wind sheltered locations.
Avalanche Summary
No new avalanche activity has been observed or reported in the past 72 hour. Increased loading with new snow and or wind will renew avalanche activity at treeline and above with full depth releases anticipated.
Confidence
Intensity of incoming weather systems is uncertain on Friday
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.