Stability is improving but there are still avalanche problems out there. If you see anything interesting, please submit an observation using our new website tool. For more details see: http://goo.gl/Tj0xPC
Confidence
Poor - Due to the number of field observations
Weather Forecast
A ridge of high pressure will persist for several days. On Sunday, expect a mix of sun and cloud, treeline temperatures around -8C, and light winds in the alpine. Monday and Tuesday will be much the same with mostly sunny conditions, treeline temperatures around -10C, and light to moderate southerly winds in the alpine.
Avalanche Summary
No new observations since the storm ended and temperatures dropped. In the Monashee/Selkirks, activity appears to have tapered off substantial on Saturday. Widespread natural avalanche activity with slides up to size 3.5 was reported on Thursday. Large slab avalanches were observed above 2000 m and numerous wet slides were observed at lower elevations in steep terrain.
Snowpack Summary
A new surface crust is expected up to around treeline elevation. At or above treeline, dense storm snow is sitting on a sun crust or surface hoar. In exposed alpine areas this new snow has been blasted around by strong southerly winds and has likely created deep and dense wind slabs in lee features. Reports from the region suggest that anywhere from 50-150 cm of settling snow overlies one or more weak layers which formed during November. Snowpack tests suggest that these weak layers are getting harder to trigger but still have the potential to produce large avalanches if triggered.
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.