An additional 20-30cm of snow has fallen, and more is forecast for Thursday. Choose conservative terrain and evaluate the lower layers in the snowpack carefully.
Weather Forecast
Thursday: 15cm of snow along the divide with moderate to strong windsFriday: Mainly cloudy with scattered flurries and cooling temperatures down to -15 overnight. Winds moderate gusting strong.Saturday: Mainly cloudy with isolated flurries.
Snowpack Summary
The snowpack in Waterton is highly variable, but you can count on a weaker structure along the divide where another 20-30cm of recent storm snow on Tuesday has formed windslabs on lee slopes which are sitting on a weak snowpack consisting of old windslabs, facets and crusts.
Avalanche Summary
As of Wednesday morning, one size 2 skier accidental was reported on Monday running on the basal facets.
Confidence
Forecast snowfall amounts are uncertain on Thursday
Problems
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.
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.