If you see more then 25 cm of new snow overnight then consider the danger rating to be HIGH.
Confidence
Moderate - Forecast snowfall amounts are uncertain on Saturday
Weather Forecast
Friday night: Snow amounts 5-20 cm with strong ridgetop winds. Freezing levels 1000 m.Saturday: Mostly cloudy with sunny periods and isolated flurries. Light winds from the SW, alpine temperatures -7 and freezing levels 1100 m.Sunday: Mostly cloudy with snow amounts 5-10 cm. Moderate winds from the S-SW. Alpine temperatures near -10 and freezing levels valley bottom.Monday: Cloudy with sunny breaks and a trace of new snow. Ridgetop winds strong from the SW. Alpine temperatures near -11.
Avalanche Summary
No new avalanche reports for Friday. On Thursday, a size 2.5 deep persistent slab avalanche was reported from the Elkford- North riding area. It was from approximately 2500 m on a SE aspect. It looked to be 24 hrs old and likely failed earlier in the storm. It did fail within the basal facets (deep persistent slab) and scrubbed down to rocks. Widespread loose dry avalanches were also noted from steep terrain features up to size 1.5. Natural avalanche activity may taper off, however; slab avalanches may be primed for human triggering.
Snowpack Summary
Another 14 cm of low density storm snow arrived overnight bringing the recent snow totals up to 80 cm in the past week. The new snow will likely have a poor bond to previous old snow surfaces that consist of stiff wind slabs, crusts and facets. Strong southwesterly winds is redistributing the new snow onto leeward slopes, building thicker and stiffer slabs. The mid-pack in this region is generally well settled and strong, but the bottom third of the snowpack is composed of weak facets (sugary snow crystals). Approximately 100-120 cm of settled snow sits above the weak layer of sugary, rotten facets that developed mid- December. This remains a concern and should be on your radar, especially with continued forecast snow and strong winds potentially overloading the weakness.
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.