Northerly winds and periods of convective flurries have created wind slabs in the alpine.
Weather Forecast
Sunny and dry for Wednesday and Thursday with freezing levels around 1500 m and light winds. A mix of sun and cloud for Friday as freezing levels reach 2000 m and winds increase to moderate westerlies.
Avalanche Summary
Reports from Monday include several dry loose sluffs in steep terrain and thin soft wind slabs reacting to slope cuts with minimal propagation.
Snowpack Summary
5- 10 cm of recent storm snow adds to the variable amounts of dry facetted snow on top of the mid-February crust with associated buried surface hoar in sheltered areas, or more recent melt-freeze crusts on sun-exposed slopes. The late-Jan crust/surface hoar layer can be found about a metre below the surface in deeper snowpack areas. The mid-January surface hoar, can be found below that. These layers have gained significant strength, and chances of triggering these weaknesses have decreased dramatically. However, triggering may be possible with a large input such as cornice fall, or an avalanche stepping down, especially on slopes that see a lot of sun.
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.