Avalanche Forecast
Issued: Dec 11th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Persistent Slabs.
Mark Herbison,
A cautious approach should be used until the snowpack has time to adjust to the new snow load. Take the time to investigate the layering before committing to your line.
Summary
Weather Forecast
Another 10-15cm of snow by Sunday morning as the Pacific 'Party' Front exits the region. Mainly cloudy skies and isolated flurries for Sunday. 25-50km/hr South West winds with an alpine high of -12. Another small pulse of snow should arrive on Tuesday with slightly warmer temps.
Check out the Mountain Weather Forecast for more details.
Snowpack Summary
30cm of low density snow in the past 24hrs, totaling 80cm of storm snow this week. Mod-strong South West winds creating fresh slabs in exposed terrain features. The Dec 1 crust is ~15cm thick at 1900m, buried by ~90cm and can be found up to 2300m. The mid and lower snowpack is generally well bonded and strong.
Avalanche Summary
A widespread natural avalanche cycle up to size 3 on Saturday as the new snow and strong winds increased the activity.
The field team observed Cheops N1 run size 2.0 to 2/3 fan, dusting the skin track in the Connaught Drainage.
Numerous reports of size 1-2 skier triggered storm slab avalanches in steep terrain and on convex rolls.
Confidence
Problems
Storm Slabs
30cm of new snow with another 10-15cm by Sunday morning with 25-50km/hr South West winds will continue to build storm slabs at all elevations. Expect fast sluffing in steep terrain and avoid wind loaded areas where storm slabs will be deepest.
- If triggered the storm slabs may step down to deeper layers resulting in large avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
50-90cm on the Dec 1 crust, which is beginning to gain enough cohesion to fail as a slab where the interface bond is weak. It is mainly an issue at treeline and below, but extends into the lower alpine region.
- Carefully evaluate terrain features by digging and testing on adjacent, safe slopes.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 12th, 2021 4:00PM
