The late October crust near the base of the snowpack is reactive to rider triggers producing large avalanches. Its possible to trigger this from a significant distance away. Heads up out there as this problem will likely persist.
Summary
Confidence
Low - Due to the number and quality of field observations
Weather Forecast
Saturday: Mostly cloudy with isolated flurries and alpine temperatures near -15. Ridgetop winds light from the North West and freezing levels at valley bottom.Sunday: Mostly cloudy in the valley with sunshine at higher elevations. Alpine temperatures near -12and freezing levels at valley bottom. Ridgetop winds light from the West.Monday: Cloudy with new snow amounts 5-10 cm. Ridgetop winds moderate from the South West. Alpine temperatures rising to 0 degrees and freezing levels near 1100 m.
Avalanche Summary
No recent avalanche activity has been reported. I suspect stiff wind slabs exist at treeline and in the alpine on leeward slopes and behind terrain features. If triggered, these wind slabs could step down and trigger deeper weak layers within the snowpack initiating large avalanches. If you get out this weekend please submit your observations to the
Mountain Information Network. Snowpack Summary
Alpine snow surfaces are likely wind affected with the average snowpack depths 80 cm -140 cm at treeline elevations, and up to 160 cm in the alpine. Approximately 30-50 cm of recent snow now overlies two crusts that were buried near the end of November. Reports indicate that these crusts extend well into the alpine and seem to be supportive to rider traffic. Below these crusts is a well settled mid pack that sits on the late October crust close to the base of the snowpack at all elevations. This late October "crust/facet combo" is widespread and has been very reactive to rider triggers producing large avalanches.
swerner,
Avalanche Canada
