Wind, new snow and warm temps have created new windslabs in the last 24 hours.
Weather Forecast
The strong westerly winds will continue overnight. Alpine temps will fall to the -7 range. Tomorrow will have isolated flurries with no significant accumulation. The winds will be 30-40km/hr from the west. While not part of our forecast, its worth mentioning the solar radiation is noticeable these days. Expect clear skies or thin cloud to have an impact on southerly exposures.
Avalanche Summary
Nothing from the last 24hrs.
Snowpack Summary
Moderate to strong SW winds have contributed to new, alpine windslabs on N-S aspects. Fortunately these are easy to spot and predict in terms of location. In terms of "triggerability", it felt as though these could be easily triggered in steep, convex terrain. Treeline also had these slabs, however they were limited to wind exposed areas. For the deeper layers, the situation is still the same as it has been. To make a long story short, the deeper layers are widespread and very difficult, if not impossible to trust. Below treeline the warm temps made for moist, sticky snow that will form a thin crust overnight.
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.