Given the recent snow and wind loading, there has been a surprising lack of avalanche activity. Until the snowpack adjusts to this new load conservative terrain choices are in order.
Weather Forecast
The next couple of days will be partly cloudy with a chance of very light flurries. Winds will be strong from the west or south-west with temperatures near -10°C. Some snow is the forecast for late Wednesday and into Thursday with accumulations near 10cm.
Avalanche Summary
A few new size 2 slab avalanches were observed in the past 48hrs. These avalanches occurred in steeper Treeline areas failing down 30-40cm. In addition, a few small loose dry avalanches have occurred over the past 2 days in steep Alpine and Treeline terrain.
Snowpack Summary
Yet another day of strong winds coupled with as much as 25cm of snow in the past few days has led to continued wind slab development in the Alpine and open areas at Treeline. At 2250m and below there are now 3 layers of buried surface hoar, which is very unusual for the Rockies. These are referred to as the Jan 18th, Jan 6th and Dec 15th surface hoar layers, down 25, 50 and 100cm respectively. Recent snowpack stability tests indicate that all these layers are reactive, with the Jan 6th and Dec 15th layers the most concerning as there is now sufficient overlying slab to be an avalanche problem. The November crust layers are still on our radar, but still do not appear to be reactive at the moment.
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.