Avalanche Forecast
Issued: Dec 9th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Persistent Slabs.
rgoddard,
Avalanche Canada
New snow will need some time to stabilize.
An increase in temperature and wind will be added more load to our buried weak layer.
Assess conditions while you travel. Watch and feel for signs of instability such as whumpfing, cracking, and recent avalanches.
Summary
Confidence
Moderate
Avalanche Summary
The new snow that fell Thursday night quickly formed a storm slab. This slab produced several avalanches up to size two that were triggered with explosives and ski cutting. Natural activity was also seen from this storm slab.
Snowpack Summary
Thursday night brought us 15 cm of fresh snow. With warmer temperatures and more water in this snow, it will feel heavier than the snow we have been getting over the last week. That snow came with southwesterly winds and was redistributed, building wind slabs. Where the wind did not have an effect, the new heavier snow will be sitting on about 30 cm of lighter snow.
The middle of the snowpack consists of weak sugary layers of facets and surface hoar. A widespread rain crust remains near the ground, at treeline, and below treeline.
At treeline, snowpack depths vary from 120 to 200 cm.
Weather Summary
Friday Night
Mainly cloudy, 5 cm accumulation, winds southwest 15 km/h, temperature -9 C at 1500 m.
Saturday
Cloudy, 8 cm accumulation, winds southwest 15 gusting to 25 km/h, temperature -5 C at 1500 m.
Sunday
Mainly cloudy, 10 cm accumulation from the night previous, possible rain during the day, winds south 20 to 30 km/h, temperature 0 C at 1500m.
Monday
Cloudy with sunny periods, trace accumulation, winds northeast 15 km/h, temperature -13 C at 1500 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Continue to make conservative terrain choices while the storm snow settles and stabilizes.
- Fresh snow rests on a problematic persistent slab, don't let good riding lure you into complacency.
- Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
- If triggered, storm slabs in-motion may step down to deeper layers and result in very large avalanches.
Problems
Storm Slabs
15 cm of new snow that fell Thursday night sits on a variety of surfaces that include a layer of low-density lighter snow. Warmer temperatures are expected to consolidate this new snow into a slab.
Small avalanches in the upper snowpack could trigger deeper weak layers, creating a larger-than-expected avalanche.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Buried layers of surface hoar and facets have been reactive to human triggers in recent days. Reactivity has been observed in sheltered areas at treeline, where the surface hoar may be preserved, and in wind-loaded areas at upper elevations, where a cohesive slab has been formed above.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 10th, 2022 4:00PM
