Confidence
Fair - Due to limited field observations
Weather Forecast
Tonight and Tuesday: A weak ridge remains, while cloud from the next approaching low will result in some increasing cloudiness Tuesday afternoon. Ridgetop winds will blow light from the South with light snowfall amounts. Alpine temperatures near -9 and freezing levels 1200 m.Tuesday night and Wednesday: A low pressure system will move inland. The bulk of this system will remain South of the border, but some cloud and light precipitation will spread into the southeastern ranges. Ridgetop winds light from the SW. Alpine temperatures near -6 and freezing levels 1600 m in the afternoon, falling to valley bottom overnight.Thursday: Generally clear and dry, with possible light snow amounts. Ridgetop winds light from the SW. Alpine temperatures near -5 and freezing levels 1700 m, falling overnight.
Avalanche Summary
On Sunday sluffing occurred from steep terrain features up to size 1.0. No new observations reported on Monday.
Snowpack Summary
Up to 40 cm of storm snow has fallen. Storm slabs have been reactive naturally, especially on slopes lee to the wind. The new snow has been transported onto lee slopes by strong west and southwest winds creating wind slabs. Cornices have grown large on ridgelines and may become weak, especially if the sun shines through. In areas unaffected by the wind, loose dry sluffs are likely.Below treeline exists a melt -freeze crust which may deteriorate in the afternoon if temperatures get warm enough. I suspect this crust is bridging and instabilities that may sit beneathMid and lower snowpack layers are generally well settled.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.
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.
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.