Regions
Banff Yoho Kootenay.
The skiing has improved dramatically due to the recent snow, however there is a poor bond at the storm snow interface which will persist for some time. Avoid larger features, and steeper terrain. There is lots of good riding on low angled terrain.
Weather Forecast
Light snow flurries with sunny breaks, light W to NW winds, and temperatures between -5 and -15'C are forecast for the next several days.
Snowpack Summary
At tree line 10 - 30 cm of snow has fallen since Dec 23, with the heaviest snowfall occurring in Yoho Park. This new snow overlies the Dec 18 layer which consists of crust, facets and/or surface hoar depending on the location. A poor bond exists at this interface. At the base of the snowpack weak crusts and facets exist which are still a concern.
Avalanche Summary
Several avalanches up to Class 2.5 (with propagations up to 200 m) were observed running in the recent storm snow in Yoho Park on Dec 24th. Lake Louise ski hill also reported several natural and skier controlled avalanches up to size 2.5 within the past 48hrs, running in the new storm snow and occasionally stepping down to the basal facets/crusts.
Confidence
Due to the number of field observations
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.