Conditions remain unpredictable with whumphing noted. Consequences of being caught would be severe. Be cautious in recently opened Caribou closure areas.
Weather Forecast
Sun and cloud with light flurries the next few days. Temperatures are cooling slightly into the -12 to -16 range. Winds may shift Northerly on Wednesday. No significant snow is expected.
Snowpack Summary
25cm new snow and warm temperatures last week at the Columbia Icefields with 35km/hr SW winds built a windslab at TL and ALP. A rain crust exists below 1900m. The dense upper snowpack overlies a weak faceted lower pack making for unpredictable and dangerous avalanche conditions.
Avalanche Summary
On Friday several size 2-3 avalanches were remote triggered by skiers a significant distance away in the McCarib Pass area. Several avalanches to Sz 3 occurred Saturday along the Parkway with one dusting the highway from Mt. Wilson. Widespread whumphing and shooting cracks were noted in the Whistler creek area on all elevations.
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.