Avalanche Forecast
Issued: Dec 8th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
rgoddard,
Avalanche Canada
Wind slabs may be reactive in the alpine and at treeline while more sheltered areas may harbour weak layers deeper in the snowpack.
Keep your terrain choices conservative and assess conditions as you travel and you should be able to find good riding.
Summary
Confidence
Low
Avalanche Summary
No new natural avalanches reported in our region. Some small size one avalanches were produced by focusing ski cutting and explosives toward wind slabs.
Looking forward, expect wind slabs to be reactive to ridder-triggering. If an avalanche is triggered, it may trigger weaker layers further down in the snowpack, producing an even larger avalanche.
We have very limited observations in the field. If you do get out please consider contributing to the MIN.
Snowpack Summary
The top layer of the snowpack consists of up to 15 cm of new low-density snow which has accumulated over the last five days. The wind has transported much of this snow with strong northwesterlies earlier in the week, switching direction to the west-southwest and calming down to moderate. The slight warming trend has also added to the likelihood of building wind slabs in the alpine and at treeline. This snow overlies a previously heavily wind-affected surface in open areas and many windward slopes may have been stripped of much of its snow.
Buried 40-60 cm down lies a weak layer comprising of surface hoar and facets. This layer has been shown to be reactive in snowpack tests.
Further down the snow is sugary and faceted with a rain crust near the ground.
Total snowpack depths at treeline elevations are 60-90 cm.
Weather Summary
Thursday Night
Cloudy with some sunny periods, 2 cm accumulation, winds southwest 30 km/h, temperature -4 C at 1500 m.
Friday
A mix of sun and cloud, 4 cm accumulation, winds southwest 25 km/h, temperature -5 C at 1500 m.
Saturday
Cloudy with sunny periods, up to 5 cm accumulation, winds southwest 20 km/h, temperature -4 C at 1500 m.
Sunday
Mostly cloudy, trace accumulation, winds southwest 15 to 20 km/h, temperature -5 to -3 C at 1500 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
Problems
Wind Slabs
Fresh and reactive slabs on leeward slopes at upper elevations have been produced.
Small avalanches may trigger a bigger avalanche by 'stepping down' to the weak and faceted crystals buried deeper within the snowpack.
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Buried layers of surface hoar and facets exist 45-70 cm down and are showing reactivity in snowpack tests. Avalanches on this layer are possible where a cohesive slab exists above it.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 9th, 2022 4:00PM
