Strong winds, warm temps are new snow have created new windslabs in alpine areas. Recent avalanche activity indicates that these slabs have the potential for triggering by light loads such as a person. Use caution and keep an eye on overhead terrain.
Confidence
Moderate - Forecast snowfall amounts are uncertain on Friday
Weather Forecast
Convective flurries are forecast to continue overnight. Winds will continue out of the SW in the strong range with temperatures in the alpine midday on Friday around -2. Friday the day is forecast to start out clear and then have clouds build in throughout the day. Freezing levels will be around 1900m
Avalanche Summary
A few new slabs up too sz 2.5 out of alpine terrain on East aspects were observed. The common theme of these avalanches was crossloaded terrain. There was also numerous loose dry avalanches up to sz 1.5 out of steep unskiable terrain.
Snowpack Summary
Up to 25cm of recent storm snow has fallen over the past 36hrs above 2300m. Snowfall amounts rapidly taper as you decrease elevation with only 5cm of snow being observed at lower elevations. The 0307 Crust is being found down 20cm at 2200m and the bond with the underlying snow is so far good. Strong winds at upper elevations on Thursday have created new winsdslabs in the upper snowpack that are reactive to skier traffic in wind affected areas.
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.
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.