Wind slabs may exist on wind-loaded slopes.
Weather Forecast
MONDAY NIGHT: Clear skies, moderate northwest winds, freezing level below valley bottom.TUESDAY: Mix of sun and clouds, moderate to strong northwest winds, alpine temperature -10 C, freezing level below valley bottom.WEDNESDAY: Mix of sun and clouds, moderate to strong west winds, alpine temperature -10 C, freezing level below valley bottom.THURSDAY: Cloudy with light snowfall, moderate to strong southwest winds, alpine temperature -5 C, freezing level rising to 1500 m.
Avalanche Summary
No new avalanches were observed on Monday. Storm slabs were reactive on Sunday, releasing both naturally and by explosives. They were generally large (size 2) and on northerly aspects with depths around 30 to 50 cm.
Snowpack Summary
Around 20 cm recent storm snow was accompanied by strong winds that blew first from the southwest and then from the northwest. This new snow covers a weak layer of surface hoar (feathery crystals), which was buried on Boxing day. This layer could be an issue in areas where the wind has blown the snow into drifts. 80 to 130 cm below the surface is an old persistent weak layer that formed in early December. This layer mostly consists of sugary facets with some isolated areas also containing feathery small surface hoar. While professionals are still tracking this layer, it has not been reactive for some time now. Near the bottom of the snowpack lies a mix of crusts and facets that formed in late October/early November. Triggering an avalanche at the base of the snowpack is unlikely at this time, although the most likely place to do so would be from a steep rocky start zone in an area where the snowpack was shallow.
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.