Warm temperatures and solar radiation may elevate the avalanche danger at higher elevations on Monday.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
Expect mainly clear skies and valley cloud for the forecast period. An inversion is forecast for all 3 days with high alpine temperatures peaking at 5 degrees on Monday and Tuesday. Winds are expected to remain light to moderate from the west.
Avalanche Summary
On Friday a few stiff wind slabs to size 1.5 were explosive-triggered at treeline. No other avalanches have been reported since. Looking forward, we should see a gradually diminishing potential for wind slab releases as warm daytime temperatures and overnight cooling promote bonding in the upper snowpack. The band of warm air associated with the inversion has been hovering at elevations higher than most peaks in the area. If this band of warm air drops, we may likely see a round of loose wet avalanche activity in steep, sun-exposed terrain.Please submit your observations to the Mountain Information Network (MIN).
Snowpack Summary
Stiff wind slabs exist on a wide range of aspects on alpine and exposed treeline slopes. In sheltered treeline and below treeline terrain, I suspect light amounts of low-density snow intermingle with surface hoar and surface facets.Roughly 30-60 cm below the surface you'll likely find a hard crust that was buried on November 26. This crust is approximately 30 cm thick and extends from 1600 m to mountain top on all aspects. Below this crust, the snowpack is moist to ground. Average snowpack depths at treeline elevations in the region range from 80-120 cm.
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.
Loose Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.