Confidence
Fair - Timing, track, or intensity of incoming weather is uncertain
Weather Forecast
Arctic air begins to influence the region Monday. No significant precipitation is expected Monday, although you may run into the occasional flurry. Temps are low; expect a daytime High of -14 & an overnight Low of -27. Winds at ridge top will be Moderate out of the SW. TL winds are expected to be light out of the E. This pattern looks to persist through at least Wednesday evening.
Avalanche Summary
Sluffing is occurring in steep terrain, but no recent avalanche activity has been reported.
Snowpack Summary
The region has received as much as 30 cm in the last 48 hours, 50 cm in the last 7 days. Much of this snow has been accompanied by strong variable winds which has created a wind-slab problem in the alpine and treeline elevation bands. Cool dry Arctic air is creeping into the valleys in the far north portion of the region. This air mass will continue to work its way south which will tighten the snowpack up a bit, drop temperatures & introduce reverse winds at and below treeline.
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 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.