A big change in avalanche hazard will occur on Tuesday as moderate snowfalls arrive with extreme SW winds. The Dec 4th weak layer will be primed for human triggering. Adjust your terrain choices accordingly.
Confidence
Moderate - Intensity of incoming weather systems is uncertain
Weather Forecast
Up to 20cm of new snow is expected through the day on Tuesday with strong to extreme SW winds. Temperatures will be mild with highs near -2 celsius in the Alpine and freezing levels near 1900m.
Avalanche Summary
Nothing new was observed today, but visibility was limited.
Snowpack Summary
5 to10cm of new snow has fallen in the past 24 hours with strong SW winds and generally warm temperatures. Between 10 and 20cm of snow now covers the Dec 4th interface of surface hoar, sun crust and facets, and the bond at this interface appears poor. Thin wind slabs have formed in Alpine and Treeline areas on lee and cross-loaded features, and further wind slab development will continue as the storm is expected to bring more snow and strong/extreme winds over the next 24 to 48 hours. The snowpack remains supportive to skier traffic above approximately 1900m, but below this ski penetration is to ground. Current snow depths:Burstall = 74cmMud Lake = 62cm
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.
Loose Dry
Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.