Regions
Banff Yoho Kootenay.
Watch for new windslab development from overnight SW wind. Surface failures and wind loading may be enough to start to trigger the Dec 15 layer lower down.
Weather Forecast
Another cold day Thursday (-15 to -20), with moderate to strong SW winds forecasted for Wednesday night. Winds will taper through the day Thursday, but pick up again Friday as the high pressure ridge moves in over area bringing warmer temperatures for the weekend.
Snowpack Summary
25-40cm of snow sits over the Dec 15 layer which consists of surface hoar, sun crust, or facets depending on location. Easy to mod shears found on this layer. Below this the snowpack is heavily faceted with remnants of older crust's still lingering throughout, but no significant shears found in the lower pack. Some isolated windslabs near ridgetop.
Avalanche Summary
A few loose snow avalanches were observed today. Surface snow showed no sign of slab characteristics today in the Sunshine and Louise areas in previously worked terrain, but we expect this to change overnight with the forecasted wind.
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.