Regions
Banff Yoho Kootenay.
Dress warm and be careful for windslabs near ridge-crests, and loose snow from steep rocky features. Ice climbers may experience loose snow pour-overs as things facet out.
Weather Forecast
Some more snow is forecast for Thursday. Amounts possibly in the 5cm range. Then it is expected to get cold. As the Arctic air pushes in wind chills are expected to be fairly high. Dress warm.
Snowpack Summary
10-30 cm of soft snow now covers the Dec 15 persistent weak layer of surface hoar, sun crust or facets (depending on location). Multidirectional winds have created windslabs near ridge-crests on many aspects. Plumes were noted in Lake Louise today.
Avalanche Summary
One shallow slab avalanche was noted behind the Hwy 1/Hwy 93N intersection.
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.