Regions
Banff Yoho Kootenay.
Dry good ski conditions continue, watch for small amounts of loading from light to moderate winds which will produce windslabs in the alpine and treeline.
Weather Forecast
For Wednesday we expect Light to Moderate Northerly winds switching to North East in the afternoon, temperatures from -15 to -5 and trace amounts of new snow.
Snowpack Summary
30 to 50 cm of snow has fallen since Feb 2. Recent new snow has been affected by Light to Moderate westerly winds. Cold conditions continue promoting faceting of the snowpack. Down 30 to 75cm, Jan 17 surface hoar produces sudden planar shears in isolated locations treeline an below. A weak basal snowpack exists in shallow areas.
Avalanche Summary
Several reports of both skier triggered wind slabs and loose dry avalanches have been noted this past week. Generally these avalanches have been small (size1-2) but have been running far, entraining the loose faceted surface snow.
Confidence
Due to the number and quality of field observations
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.
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.