Summary
Confidence
Fair - Intensity of incoming weather is uncertain
Weather Forecast
Saturday: Mostly clear skies / light southwest winds / freezing level at 1900m Sunday: moderate precipitation intensifying to heavy overnight / strong southwesterly winds / freezing level at about 1900m Monday: moderate precipitation / strong southwesterly winds / freezing level at about 2200m
Avalanche Summary
A fairly widespread natural windslab avalanche cycle to size 2 took place on Friday in response to localized heavy loading on Thursday evening. I expect ongoing storm snow activity with a shift to more widespread wet snow instabilities with warming forecast for the weekend.
Snowpack Summary
On Thursday, moderate to locally heavy accumulations formed wind slabs at treeline and above on a variety of temperature-affected surfaces that include well settled powder, wet grains and crust sandwiches. Rain has continued to penetrate and weaken the isothermal snowpack at lower elevations. The mid-February buried surface hoar layer is down about 140-220 cm, although avalanches releasing on this layer represent an extremely low probability-high consequence scenario. Cornices in the region are very large. With spring temperatures, and direct solar radiation these are more likely to become weak and fail. They could provide a large enough trigger to release deep layers on slopes below. Average snowpack depth in the alpine remains in the 3 m range. For more information on Spring Conditions and ways to mitigate risk, please visit the new Forecasters Blog Post.
jlammers,
Avalanche Canada
