Regions
Banff Yoho Kootenay.
Decent skiing can be found in sheltered locations. Due to the variability in the snowpack, we are still treating larger alpine features with caution. SH
Weather Forecast
Light to mod. N winds in the alpine for Saturday with lows around -25C and highs in the -15C range. No snow in the forecast except for a trace on Sunday.
Snowpack Summary
5-15cm of snow has buried the Jan 30th surface hoar / sun crust layer. This new snow came in with very little wind, but there have been some soft storm slabs building in the immediate lees of S through SE ridgetops. The basal facets remain weak, but the overall snowpack is gaining strength.
Avalanche Summary
No new avalanches observed in the past several days.
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.
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.