Still not the time to ski big lines despite Moderate rating. Lots of variability across the landscape with a lurking basal weakness. Shallow locations are the likely trigger spots. Human triggered avalanches are possible on specific terrain features.
Weather Forecast
Mostly dry the next few days with possibly very light snow Tuesday and Wednesday. Temperatures will range from -3°C in the afternoons to -12°C at night. Light winds from the WSW on Mon night into Tuesday diminishing to calm by Wed morning.
Snowpack Summary
Snowpack below treeline is 85cm deep, low density snow with a 20-40cm stiffer midpack over weak basal facets. It remains the weakest of our elevation bands as not much bridges the basal facets. Above TL, snowpack ranges from 10 to 130cm where a thicker midpack bridges the basal facets. Variable wind slabs present with the previous aggressive winds.
Avalanche Summary
Natural activity has tapered off. Thursday's control work on the Icefields Parkway yielded large avalanches to size 3 on all alpine aspects releasing on either the storm snow interface or on basal facets.
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.
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.