Regions
Banff Yoho Kootenay.
Touchy conditions persist. Give those deep layers some time to adjust to the new load.
Weather Forecast
Warmer temperatures and some light precipitation are coming Wednesday and into Thursday. Only 5- 15 cm is expected by end of day Thursday. Winds will be moderate to strong SW on Wednesday night/ Thursday. Friday should see a clearing and cooling trend with the winds dyeing down.
Snowpack Summary
Up to 70 cm of snow of recent snow with variable wind effect has put a dense load over the persistent weak layers. In thicker snow pack areas, the Dec. 10th weak layer of facets is now down 100-150cm with a stronger snowpack below. In thin snowpack areas, the Dec.10th layer is mixed in with the basal facets and October crust.
Avalanche Summary
The natural avalanche cycle has tapered off, but conditions are still primed for human triggering. A localized natural cycle in the Sunshine area was likely triggered by winds, showing how touchy it still is in many areas. In the Lake Louise area, a small but deep slab was triggered just outside of the ski hill boundary in a small treeline opening
Confidence
Due to the number and quality of field observations
Problems
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.