Regions
Banff Yoho Kootenay.
Backcountry conditions have improved dramatically with an additional 20 cm of light powder. This is fluffy stuff with little cohesion; ice climbers should expect sluffs and skiers should be alert for blowing snow which will change things immediately.
Weather Forecast
Westerly flow continues with the storm track now positioned directly over the area. No significant systems embedded for the next few days, so expect light flurries with only a few cm of accumulation for Tuesday and Wednesday. Light winds continue to be forecast. A significant system will cross the region on Thursday with of 20 cm expected by Sat.
Snowpack Summary
20-25 cm low density snow now sit on the Jan 30 crust. The dominant feature of the last 24-hours has been light winds and cold, dry snow with minimal windslab formation, but we expect isolated pockets of soft slab above 2300 m. The very weak base of depth hoar continues to dominate the region, with moderate compression test 25 cm above the ground.
Avalanche Summary
Loose snow sluffing from cliff areas was observed today, but no new slab avalanches were reported or observed.
Confidence
Wind speed and direction is uncertain
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.