Avalanche Forecast
Issued: Dec 10th, 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
Be on the lookout for changes in the snow as you transition into wind-affected terrain.
Use the terrain to your advantage in accessing the best and safest riding.
Summary
Confidence
Avalanche Summary
An avalanche, size two, produced naturally from a wind slab was reported in our area. Suspect the possibility of more of these as you travel through the backcountry. Regional neighbours are also reporting evidence of avalanches produced from the weaker layer further down in the snowpack.
Snowpack Summary
In the last 36 to 48 hours southwest winds have been transporting the up to 15 cm of new snow that fell during this time period as well. New snow and new wind slabs are sitting on older wind slabs that were created from strong westerly winds that occurred earlier in the week.
A buried layer of surface hoar sits 20 to 30 cm deep and remains a layer of concern, especially once a stiffer slab becomes established above it.
Generally speaking, we have a thin snowpack that has experienced a period of prolonged cold temperatures. The combination of the two has created a weakened snowpack by promoting faceting as a whole.
The overall height of snow is highly variable throughout the region with around 40 to 140 cm in the alpine.
Weather Summary
Saturday Night
Cloudy with clear periods, 2 to 4 cm accumulation, wind southeast 20 km/h, -7 C at 1500 m.
Sunday
A mix of sun and cloud, trace accumulation, winds southeast 15 km/h, -5 C at 1500 m.
Monday
Cloudy with sunny periods, trace accumulation, winds northeast 10 km/h, -6 C at 1500 m.
Tuesday
A mix of sun and cloud, no accumulation, winds northeast 10 km/h, -10 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.
- Be especially cautious as you transition into wind affected terrain.
Problems
Wind Slabs
Wind slabs may have formed with our consistent but smaller amounts of accumulations and southwest winds.
These slabs likely overlay a weak, sugary lower snowpack. If triggered, small avalanches may trigger a bigger avalanche by 'stepping down' to these weak crystals.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Buried layers of surface hoar and facets are still a concern as more load is added. Suspect triggering to be its highest in areas where the snowpack is shallower.
This layer will be most evident in sheltered areas at treeline, where surface hoar may be preserved, and in wind-loaded areas at upper elevations where a cohesive slab above has formed.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 11th, 2022 4:00PM
