Forecast warm temperatures, sunny skies, and high freezing temperatures are expected to weaken windslabs and cornices in the alpine.
Summary
Confidence
Fair - Timing or intensity of solar radiation is uncertain
Weather Forecast
Mix of high cloud and clear skies overnight with moderate southwest winds and freezing levels dropping down to about 1400 metres. Some warm air (slightly below freezing) may remain at higher elevations overnight. Tuesday mostly sunny with a chance of high cloud combined with light southwest winds and freezing levels rising up to about 2300 metres. Cloudy with light – moderate precipitation on Wednesday with moderate southwest winds and freezing levels around 1900 metres. Mix of sun and cloud on Thursday with light winds and 1800 metre freezing levels.
Avalanche Summary
Several reports of windslabs up to size 1.5 on various aspects in the alpine that were 20-30 cm deep.
Snowpack Summary
Variable recent storm snow totals across the region are generally in the 5-25 cm range. The snow surface varies with elevation and aspect with respect to sun and wind exposure, and includes dry new snow, loose facetted snow, wind slabs, and sun crusts. The mid-February crust is down around 10-30 cm where it is not wind loaded or scoured. The late-Jan crust/surface hoar layer (up to 100 cm deep) and the mid-January surface hoar (80-120 cm deep) are generally dormant, and chances of triggering these weaknesses have decreased. However, triggering may be possible with a large input such as cornice fall, or an avalanche stepping down, especially on slopes that see a lot of sun.
triley,
Avalanche Canada
