Sporadic avalanche activity (both natural and human-triggered) has occurred over the past few days and forecasters have low confidence in the snowpack. Conservative route selection is strongly recommended. This is NOT the time to ski the big line.
Weather Forecast
Cloudy conditions are expected through the week with light to moderate snowfall possible Tuesday nd Wednesday. Monday should see temperatures near -7 degrees in the Alpine and generally light winds.
Avalanche Summary
Visibility was limited today, but the skier-triggered avalanche from yesterday on Mt Engadine was evaluated from a distance. We still have limited information on this slide, but it occurred on a W to NW aspect at Treeline and was a size 2.5 that took out the entire width of the normal avalanche path and flowed to at least 3/4 of the run-out.
Snowpack Summary
Storm snow from the past week has settled to an average of 30cm at treeline. Sun crusts are found on solar aspects. Recently formed wind slabs are evident in the Alpine and open areas at Treeline, but so far these seem relatively well bonded to the previous surfaces. The Feb 10th layer remains a concern and is found buried 80 to 120cm. This layer continues to give variable results in snowpack tests and has caused sporadic natural avalanche activity over the past week.
Problems
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.
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.