It feels like late spring in the valley and mid winter in the alpine. Don't let the conditions at the parking lot lull you in to being complacent.
Weather Forecast
Temperatures remain relatively cool, with 10-15cm of snow forecast for Friday night into Saturday morning accompanied by moderate SW wind. Skies clear by Saturday evening as the winds shift to being more westerly. Cloudy skies return for Sunday afternoon as the trailing end of a weak front brings flurries and ongoing westerly wind into Monday.
Snowpack Summary
Up to 50mm in the past week, accompanied by warm temperatures and strong SW winds. This has left in it's wake a well settled snowpack below treeline; a couple of buried crusts, down as deep as 30cm and 50cm (widespread below 2200m and extending into the alpine on solar aspects), and several layers of stiff windslab in the alpine and at treeline.
Avalanche Summary
A few natural size 1-1.5 avalanches occurred Thursday night into Friday morning out of N-E facing terrain at treeline, these are suspected to have been windslabs.
Confidence
Intensity of incoming weather systems is uncertain
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.