Remote skier triggering of avalanches continue amongst our nearest neighbors. The weak base will persist for sometime. Cautious decisions are key as avalanche consequences would be severe.
Weather Forecast
Light snow this week with light NW winds shifting Easterly on Friday. Seasonal temperatures dipping to -18 on Friday.
Snowpack Summary
25cm snow last week at the Columbia Icefields with 35km/hr SW winds built windslabs at TL and ALP. Winds continue light to moderate from SW. A rain crust is below 1900m. A dense upper snowpack overlies a weak faceted base making for unpredictable dangerous avalanche conditions. Feb 10 SH layer may be 40cm deep yet its reactivity remains dormant.
Avalanche Summary
No patrol on Monday or Tuesday. SAR team busy in Mcbride on rescue. On Feb 17 several size 2-3 avalanches were triggered by skiers from a significant distance away in the McCarib Pass area. Widespread whumphing and shooting cracks were noted in the Whistler creek area recently.
Confidence
The weather pattern is stable
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.