A good refresh out there, but watch for loose dry avalanches in the Alpine. These are running far and could be hazardous in the wrong terrain feature.
Weather Forecast
Thursday should be mostly clear with light winds and temperatures climbing to near -9 by early afternoon. Friday and Saturday should be snowy with as much as 20cm on the way, but stay tuned for updates as we get closer to the expected precipitation event.
Avalanche Summary
Several naturally triggered loose dry avalanches occurred overnight with the new snowfall. These slides were found mostly in steep Alpine terrain on N and E aspects, ranging in size from 1.0 to 2.0 and notably running quite far down slope.
Snowpack Summary
10cm of new snow fell overnight, which is being re-distributed at upper elevations by light to moderate SW winds. Previously formed wind slabs are widespread on all aspects in the Alpine. These vary from being potentially reactive to skier traffic, to being completely "welded" in place. In other words, there is lots of variability out there. With the prolonged cold period the snowpack is facetting and loosing strength. However, in many areas, particularly deeper snowpack zones, the midpack is very dense and is providing lots of bridging strength over the weak basal facets. Though a full-depth avalanche is unlikely, if it does occur it will be catastrophic. Large triggers, such as a cornice failure, or triggering from a shallow snowpack area, are possible ways to wake up the deep persistent weak layer.
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.
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.