Summary
Confidence
Fair - Forecast snowfall amounts are uncertain on Saturday
Weather Forecast
SATURDAY: Light to moderate amounts of snow in the overnight period Friday into Saturday with continued moderate accumulations throughout the day. Winds moderate to strong from the west and southwest. Temperatures gradually dropping as cold air invades from the north. SUNDAY: Light amounts of snow in the early part of the day and colder temperatures. Winds light to moderate from the north. MONDAY: Cold and clear throughout the day.
Avalanche Summary
Recent activity seems to be isolated to WSL in alp and TL areas. Sc and Sa to 1.5. Reports of most recent HST settling into slab. small pockets triggering.
Snowpack Summary
Recent light amounts dry snow has maintained the snow supply for fresh wind slab development and cornice growth. Surface condition in wind-exposed areas is highly variable with scoured areas, sastrugi, and pockets of fresh hard and soft wind slabs. A weak graupel and/or stellar layer down 25-30cm appears to have been the culprit in recent wind slab avalanche activity. Avalanche professionals are gaining confidence in the mid-December persistent weakness, now down 90-170cm, but concern remains for heavy triggers, such as cornice drops, on steep unsupported slopes. When this persistent weaknesses is combined with weak wind slabs, thin trigger points, and other weaknesses within and under the recent storm snow and at the base of shallow snowpack areas, the result is a highly variable snowpack with the potential for step-down deep slab avalanches.
mbender,
Avalanche Canada
