Avalanche Forecast
Issued: Dec 10th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
Garth Lemke,
Despite the lack of natural activity, there is a lot of new snow present. Remember Moderate means human triggering remains possible.
Summary
Weather Forecast
Cooler temperatures, no snow, calm to light winds and mostly clear skies are forecasted for the next few days.
Snowpack Summary
40cm of storm snow from Dec 8th with moderate SW winds resulted in mainly ridgetop or exposed treeline wind slabs. The snow is settling. It overlies a variety of surfaces like hard slabs in the alpine and treeline, facets and isolated surface hoar at treeline, and crusts on steep solar aspects. The depth of the Nov 4th rain crust is 60-80cm down.
Avalanche Summary
Wednesday noted numerous loose dry natural avalanches size 1.5 on all aspects and elevations and explosive control resulted in a few slab avalanches size 2 and one size 3 on a Northeast alpine feature. Thursday's patrol noted no new avalanches and the visibility was excellent.
Confidence
Due to the number and quality of field observations
Problems
Wind Slabs
Tuesday's 40cm storm had some moderate Southwest winds which loaded some slopes into windslabs.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
Aspects: North, North East, East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
The Nov. 4 crust is down 60cm to 80cm at tree line. Wind slabs potentially could step down to this layer or even deeper to the basal instability creating large destructive avalanches. Caution at thick to thin snowpack areas.
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 11th, 2020 4:00PM
