The Maligne Road will remain closed through the weekend for avalanche control. The Icefields Parkway is currently closed due to road conditions; Expected opening is Sunday afternoon by 12:00. Call 780-852-3311 or visit www.511.alberta.ca for info.
Weather Forecast
Snowfall expected to resume Saturday night, bringing as much as 20cm by Monday morning. Precipitation will then taper off with clearing skies midweek with light SW winds before a significant pressure drop and another storm late in the week. Freezing levels to remain below 1800m throughout the week. Solar radiation gaining strength.
Snowpack Summary
Total storm snow over the Mar 15 interface is approx. 45 cm but quite variable. Open areas in the southern forecast area are showing more surface wind effect. The Mar 15 interface is weak made up of facets over variable surfaces depending on aspect and exposure. Little slab development has been observed to date.
Avalanche Summary
One skier accidental size 2.5 slab was reported from Thursday afternoon in the Shangri-La area. Road patrols in the Columbia Icefield Area on Saturday reported a size 2.5 storm slab on an East aspect at 2400m and several smaller storm slabs (sz 1) on steep alpine terrain. Solar aspects were shedding in the afternoon when the sun came out.
Confidence
Timing or intensity of solar radiation is uncertain
Problems
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.
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.
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.