A persistent weak layer of faceted snow that developed during the cold dry period in mid November exists on aspects that face W-N-SE. The greatest danger exists on slopes facing NW-N-E, where wind drifted snow has built thick slabs on top. These hard slabs are 1-4' thick and can produce very large, deep, and potentially deadly avalanches. Out of the wind zone an active weather pattern throughout December has stacked plenty of storm snow and built a cohesive and well connected slab on top of the weak, sugary, faceted snow. This weak layer has become less reactive in recent stability tests (for more details see my obs from Monday). Obvious signs of instability are becoming harder to find each day. What hasn't changed is the poor snowpack structure. Likely places to trigger an avalanche right now include:

You can avoid this avalanche problem by keeping your slope angles below 30 degrees, ride slopes that are heavily anchored by dense trees, or ride South facing slopes that do not harbor this dangerous persistent weak layer.

This video was shot Monday 12-19.

On Tuesday afternoon winds out of the South picked up intensity and starting blowing and drifting snow. Overnight the winds have shifted and are blowing out of the WNW. Westerlies will be on the increase today with the strongest winds occurring tonight. Look for fresh wind drifts to be developing above tree line today. Fresh drifts will be shallow and sensitive. Newly formed wind slabs tend to be more reactive to skier triggering. Any triggered wind drift has the potential to step down and trigger a deeper and more dangerous avalanche, especially on previously loaded slopes that face NW-N-E.