Wind slabs at upper elevations are the main concern. Seek out soft snow sheltered from recent winds.
Winds have drifted recent snow into slabs on leeward features that may be possible to trigger. Areas where wind slabs have formed overlap with areas where cornices may be reaching their breaking point.
Wednesday night: Cloudy, isolated flurries with trace accumulations, light west winds, alpine temperature -10 C.
Thursday: Cloudy, isolated flurries with trace accumulations, light southwest winds, alpine high temperature -6 C.
Friday: Cloudy, isolated flurries with trace accumulations, light variable winds, alpine high temperature -6 C.
Saturday: Cloudy, 5-10 cm of snow, light northeast winds, alpine high temperature -5 C.
Since the weekend storm, there have been a few reports of small storm and wind slabs from human triggers, in addition to several reported dry loose avalanches.
During the weekend storm, numerous large (size 2-3) avalanches released naturally in the storm snow. These avalanches primarily occurred on leeward aspects at treeline and alpine elevations. A large cornice fall was reported Sunday on a north aspect at 2400 m, and it stepped down to a large slab avalanche. Below tree line, large wet loose avalanches were releasing naturally on Friday and into Saturday.
With continuous stormy weather over the past week, there have been a handful of very large (size 3-4) avalanches breaking on deeply buried weak layers on slopes above 2000 m. Although the likelihood is decreasing in the aftermath of the storm, wind slab avalanches or large cornice fall may have the potential to step-down to these layers.
Ongoing snowfall since the weekend storm has totaled 20-40 cm. Human-triggered avalanches may be possible where this snow is being drifted by wind onto leeward features at upper elevations. Cornices are large and looming and may be reaching their breaking point.
40-70 cm of snow fell during the weekend storm above 1900 m. Extreme winds originating from the southwest and shifting to the northwest redistributed the snow onto lee aspects near and above treeline and accelerated cornice growth. During a warming event Saturday night, rain saturated snow surfaces up to around 1900 m that have since formed a crust.
The mid and lower snowpack is generally well settled and strong. Although isolated, there are two deeper layers that may still persist. A weak layer of surface hoar buried 90 to 170 cm deep may be found in the north of the region and a facet/crust layer from November near the ground may be found in shallower snowpack areas.
