Above 2300m recent wind slabs are sensitive to human triggering. With another 10 to 15cm of new snow in the next 24hrs with strong SW winds, the danger level is pushing into the "upper end" of CONSIDERABLE. Keep an eye on localized conditions.
Confidence
Fair - Timing, track, or intensity of incoming weather is uncertain
Weather Forecast
10 to 15cm of new snow are possible in the next 24hrs. Winds will remain strong to moderate out of the SW. Temperatures will range from -10 to -16 on the alpine on Monday.
Avalanche Summary
Nothing new.
Snowpack Summary
Soft slabs are prominent at treeline and are increasing in stiffness, indicating a higher likelihood of human triggering. In the alpine hard slabs are widespread with pockets of soft slab in lee and cross-loaded gully features. Extensive wind transport was occurring at upper altitudes due to strong SW winds. Snowpack tests today at treeline indicate a weakness down 35cm that failed in the easy range. Another shear also appeared down 80cm, but this was in the hard range. Below 2100m the snowpack is very weak and facetted.
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.
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.