Avalanche Forecast
Issued: Dec 12th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Loose Dry.
DH,
Avalanche Canada
A persistent weak layer sits at the ideal depth for large human triggered avalanches.
The safest way to manage this problem is through conservative terrain choices.
Summary
Confidence
Avalanche Summary
Sporadic human triggered avalanches continue to occur. On Tuesday a group triggered a size 2.5 which showed wide propagation across terrain features on Ursus Minor. Several days prior a size 2 was remotely triggered by a group 20m away near Balu Pass.
Snowpack Summary
30cm of low density recent snow sits over a rain crust up to 2100m and settled snow above this elevation.
A weak layer (Dec 1 surface hoar) buried 70-100cm deep continues to produce 'sudden' results in snowpack tests and human triggered avalanches.
The base of the snowpack is facetted at upper elevations.
Weather Summary
The ridge of high pressure maintains dry weather on Wednesday before light snowfall arrives on Thursday with light to moderate winds.
Wednesday: Sun and cloud, moderate S winds, high of -2 °C, freezing level 1500m.
Thursday: Snow 10cm with light SW winds, low -8°C high of -5 °C, freezing level 1400m.
Friday: Sun and cloud, low -7°C high of -3 °C, light S winds, freezing level 1200m.
Terrain and Travel Advice
- Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
- Loose avalanches may start small but they can grow and push you into dangerous terrain.
- Early season avalanches at any elevation have the potential to be particularly dangerous due to obstacles that are exposed or just below the surface.
Problems
Persistent Slabs
A buried persistent weak layer sits at the ideal depth for human triggered large avalanches at tree line and in the alpine and remains reactive. Below 2100m this layer is bridged by a supportive rain crust (felt by pole probing) in the upper snowpack.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Loose Dry
The low density surface snow is easily initiated in steep terrain running fast and gathering surprising mass, especially where it runs over the crust. Even small sluffs can quickly grow enough to push you into dangerous terrain.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Valid until: Dec 13th, 2023 4:00PM
