Regions
Banff Yoho Kootenay.
Winds and cold temperatures have created many weak areas in the alpine and treeline elevations this year. This gives us low confidence in the snowpack in bigger terrain at these elevations. Good skiing can still be found on sheltered non solar slopes
Weather Forecast
A weak front is forecast to bring up to 5 cm of snow with light winds Wednesday overnight with valley temperatures in the -5 to -10 range. On Thurs and Fri we will return to high pressure with sunny skies and lows in the -15 to -20 range. Likely, we will get temperature inversions (temperatures colder in the valleys than in the alpine).
Snowpack Summary
The Jan 25th surface hoar layer is buried under 5 cm of snow in the Bow Summit area, but remains on the surface in most of the forecast region. This will become a weak layer to watch in the future. Strong solar radiation has formed a suncrust on S & W facing slopes. The basal facets remain weak, but the overall snowpack is gaining strength.
Avalanche Summary
No new avalanches observed in the past several days.
Confidence
Due to the number 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.