A strong inversion is developing, which may not be obvious when you are trapped below the valley cloud in the cold air. Keep in mind that solar aspects are heating up above you.
Weather Forecast
A strong temperature inversion, with high solar radiation and alpine temps rising above 0 (potentially to +8 'C !), is forecast through Sunday. Valley cloud and cooler temps are expected at lower elevations.
Snowpack Summary
~5cm has buried, and will help preserve, a new surface hoar layer ("Jan 22"). This layer will be one to watch as it gets buried deeper. It sits on a sun crust on steep solar aspects and windslabs above treeline. The mid-pack is well settled. The Nov surface hoar, down 180cm, has spotty distribution. The base is weaker than the rest of the snowpack.
Avalanche Summary
Size 1.0 sluffs and soft slabs have been skier triggered from steeper (>35 degree) slopes running on the Jan 22 surface hoar. Along the highway, a few slabs to size 2 continue to be observed daily from steep terrain on all aspects. Small, loose solar triggered avalanches have also been observed.
Problems
Loose Dry
Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.
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.