Regions
Banff Yoho Kootenay.
Alpine danger will be dictated by the amount of wind transport Sunday. Lots of low density snow to blow around. It looks to be another cold and sunny day. SH
Weather Forecast
The arctic air continues Sunday through the first part of next week. Lows will be in the -20's with decreasing alpine NW winds and sunny skies.
Snowpack Summary
15-30cm of recent storm snow with some alpine wind effect sits over the Dec.15 layer. This weak layer consists of surface hoar (at tree-line and below), sun crust or facets (depending on location). Mod shears have been observed on this interface.
Avalanche Summary
A loose dry size 1.5 was observed on Rogan's Gully today. A piece of fresh cornice broke off from wind loading and triggered the slide. It did not go over the climb. No other natural activity was noted.
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.