Regions
Banff Yoho Kootenay.
The winds have scoured open windward areas and created some thin fresh wind slabs. Otherwise the snow is generally stable. JBW
Weather Forecast
A storm tracking along the US border will bring some snowfall and SW winds. We may see 10 cm over higher terrain Monday. Tuesday a short lived ridge will clear out the skies.
Snowpack Summary
Mod-Strong winds over the last 24 hrs have produced some thin fragile hard slabs on immediate lee terrain at and above treeline. Elsewhere the snowpack is weakening with facetting predominating, but there is still good midpack support. The Nov. Crust is giving inconsistent results as it is faceting.
Avalanche Summary
Some very small skier controlled slabs on north and east ridges with the new thin wind slab development, otherwise no new avalanches in the last 24 hrs.
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.
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.