We’ve removed the deep persistent problem from the forecast region due to a lack of recent avalanche activity. The layer still exists in the snowpack (see snowpack summary) and could be reintroduced as a problem in the future.
Strong to extreme winds with light flurries on Thursday formed wind slabs 10-30 cm thick in alpine and treeline lees. There is some uncertainty whether this problem is still a concern at treeline elevations.
An Arctic air mass has settled over the region, with forecasted low temperatures dropping to -25°C on Saturday night. Clear skies and light to moderate northerly winds are expected on Sunday.
Minimal natural avalanche activity was observed during a flight across the forecast region on Friday. Avalanche control Friday triggered very few slab avalanches, with no failures on the deep persistent problem. The majority of results were loose dry avalanches, which entrained the faceted snowpack and ran far down the paths.
Recent strong winds and snow have created winds slabs on lee features in the alpine and at treeline. The upper pack may have a thin crust under the new snow on solar aspects and a surface hoar/facet interface under last week's snow, but no avalanches observed on this layer yet. The mid-pack is generally strong; however, a facet layer can be found near the ground in shallow snowpack areas. At treeline, average snowpack depth ranges from 120 to 150 cm.
