Avalanche Forecast
Issued: Dec 25th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
zryan,
Avalanche Canada
Uncertainty around buried weak layers is best managed through conservative terrain choices.
Avoid wind-loaded areas and steep open slopes where buried surface hoar may be preserved.
Summary
Confidence
Low
Avalanche Summary
Over the weekend in the neighboring region to the east, many large (size 2 to 3) natural and rider triggered (some remotely triggered) persistent and deep persistent slabs were reported in the alpine and treeline.
We are unsure if the same deep persistent slab problem exists in this region, and this uncertainty is best managed though conservative terrain choices.
Moving forward, natural avalanche activity may taper, but large human-triggered slabs remain possible.
Snowpack Summary
Recent storm snow has been redistributed into wind slab near ridge crests by strong winds. Below treeline a new crust is on or near the surface.
The mid pack contains several layers of note; a layer of surface hoar and a crust down 20 to 40 cm, a significant crust from the early December rain event down around 50 cm and a layer of surface hoar down 50 to 90 cm.
The make up of the lower snowpack is variable throughout the region, in shallower snowpack areas, basal facets may exist.
Weather Summary
Monday Night
Increasing cloud cover with isolated flurries. Alpine wind south 50 to 90 km/h. Treeline temperature -4 °C.
Tuesday
Cloudy with snowfall, up to 5 cm of accumulation. Alpine wind southwest 50 to 90 km/h. Treeline temperature -5 °C. Freezing level rising to 1000 m.
Wednesday
A mix of sun and cloud with isolated flurries. Alpine wind southeast 40 to 80 km/h. Treeline temperature rising to -2 °C. Freezing level at valley bottom rising to 1400 m.
Thursday
Cloudy with snowfall, up to 5 cm of accumulation. Alpine wind southwest 40 to 90 km/h. Treeline temperature -2 °C. Freezing level 1400 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Use careful route-finding and stick to moderate slope angles with low consequences.
- Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
- Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
Problems
Wind Slabs
Wind slabs have formed on lee features in exposed terrain at treeline and above. Avoid wind-loaded areas and watch for fresh, reactive slabs forming throughout the day.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
A layer of surface hoar is down 50 to 90 cm and is still concerning where a significant crust is not found above it.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 26th, 2023 4:00PM
