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
Fair - Due to the number of field observations
Weather Forecast
A ridge of high pressure will persist for several days. On Sunday, expect mostly sunny conditions, treeline temperatures around -4C, and light winds in the alpine. Monday and Tuesday will be much the same with mostly sunny conditions, treeline temperatures around -8C, and light winds in the alpine.
Avalanche Summary
Initial reports from Saturday suggest that avalanche activity has tapered off since the storm ended and temperatures dropped. On Friday there was isolated activity including a natural size 2.5 wind slab and some explosive triggered storm slabs to size 1.5. Widespread natural avalanche activity up to size 3 was reported on Wednesday and Thursday.
Snowpack Summary
The rain soaked snow surface has now refrozen with colder temperatures. A thick supportive crust is expected to around treeline and a breakable crust is expected in the lower part of the alpine. The highest elevations of the alpine may still have dry snow on the surface but this has likely been heavily wind-affected by recent strong southerly winds. A thick rain crust with facets from early November is buried over 1 m down. Snowpack tests on this deep weak layers are showing improving results, but in some locations these layers are still reactive and have the potential to release large slab avalanches.
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.