The next storm system is forecast to arrive on Thursday. Game on......again.
Weather Forecast
The next storm system arrives on Thursday. Forecast models are predicting anything from 25cm to 90cm by the end of the weekend in the Icefields area. With this precipitation amount, strong westerly winds and rising temperatures the avalanche hazard will be increasing.
Snowpack Summary
Last weeks's warm temperatures and rain resulted in a crust up to 2100m on all aspects. Higher elevations have wind affected surfaces in exposed areas and wind slabs on lee aspects. More snow has fallen in the northern part of the forecast area in the last 24 hours than in the south.
Avalanche Summary
Field team in the Icefields area today reported three size 2 and one size 2.5 slab avalanches in cross loaded features in the alpine. The size 2.5 stepped down to the November basal facet layer.
Confidence
Timing, track, or intensity of incoming weather system is 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.