Wind slabs and cornices are possible at higher elevations. Be cautious as you climb and continually reassess conditions.
Confidence
Moderate - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
THURSDAY: Cloudy with light afternoon flurries (5-10 cm), strong southwest wind, freezing level around 2200 m.FRIDAY: Wet flurries increasing overnight (3-6 cm), moderate southwest wind, freezing around 2200 m.SATURDAY: Clearing throughout the day, strong southwest wind, freezing level dropping to 1500 m.
Avalanche Summary
On Wednesday, explosive control produced two small wind slabs in steep alpine terrain in the southeast part of the region. Numerous small loose wet avalanches were observed on steep solar aspects on Tuesday. Increasing wind speeds could build fresh wind slabs and warming may irritate cornices.
Snowpack Summary
The snowpack has entered a daily melt-freeze cycle. Hard crusts form overnight and become moist surface snow during the heat of the day. The exception is north-facing alpine terrain, where about 20 cm of recent dry snow and isolated wind slabs may exist. The bottom third of the snowpack is composed of weak facets, but this deep persistent weakness has not been reactive for a few weeks.
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.
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.