Avalanche Forecast
Issued: Dec 27th, 2024 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Persistent Slabs.
Avalanche Canada,
Avalanche Canada
There's no doubt that new snow and wind will form fresh, reactive storm slabs. Uncertainty lies deeper in the snowpack where dangerous weak layers may be at play.
Summary
Confidence
Moderate
Avalanche Summary
On Thursday, skiers near Rossland remote-triggered storm slabs (size 1-2) on north-facing treeline and below treeline terrain. Natural storm slabs up to size 2 were also observed in the area. Explosive control near Nelson produced storm slabs up to size 2 on a variety of aspects at treeline.
No new persistent slab activity has been reported since the storm, but observations remain limited.
Snowpack Summary
Continued snowfall adds to 15 to 40 cm of recent new snow. Accompanying southwest wind will redistribute this new snow, forming deeper deposits on leeward slopes at higher elevations.
A crust is present near the surface at lower elevations.
The upper snowpack continues to settle and bond well following significant snowfall over the last two weeks.
Weak layers of surface hoar or facets and a crust may persist in the mid-snowpack, and snowpack tests continue to indicate potential instability.
The lower snowpack is generally strong and well-bonded.
Weather Summary
Friday Night
Cloudy with 5 to 10 cm of new snow. 10 to 30 km/h southwest ridgetop wind. Treeline temperature -6 °C.
Saturday
Cloudy with 5 to 15 cm of new snow. 15 to 40 km/h southwest ridgetop wind. Treeline temperature -5 °C.
Sunday
Cloudy with up to 5 cm of new snow. 5 to 15 km/h northeast ridgetop wind. Treeline temperature -5 °C.
Monday
A mix of sun and cloud with isolated flurries. 10 to 30 km/h west ridgetop wind. Treeline temperature -7 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- In times of uncertainty, conservative terrain choices are our best defense.
- Storm slabs in motion may step down to deeper layers resulting in large avalanches.
- Surface hoar distribution is highly variable. Avoid generalizing your observations.
Problems
Storm Slabs
Recent snowfall and southwest winds have formed fresh storm slabs that will be deepest and most reactive in wind-loaded areas.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
Buried weak layers of surface hoar and facets on a crust are now buried 40 to 120 cm deep. Increased load from new snow may make these layers more reactive. Be especially cautious on steep, open slopes at treeline and below.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 28th, 2024 4:00PM
