Avalanche Forecast
Issued: Jan 1st, 2024 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Deep Persistent Slabs.
ahanna,
Avalanche Canada
Uncertainty around buried weak layers is best managed through conservative terrain choices. Check out this blog post for some insight into the current shallow yet complex snowpack.
Summary
Confidence
Avalanche Summary
On Sunday, a skier was uninjured after accidentally triggering a size 2 deep persistent slab on basal facets over a smooth rock slab.
Ongoing explosive control work in recent days has consistently produced deep persistent slab avalanches size 1.5-2.
Snowpack Summary
A skiff of new snow rests on old surfaces including surface hoar, facets and crusts. Beneath lies a complex snowpack with several layers on our radar.
The most prominent is a layer of surface hoar buried 20-50 cm deep. It is less of a concern in areas where a strong, supportive crust exists above the surface hoar layer.
The mid and lower snowpack are typically characterized by sugary, facetted crystals and a basal crust.
Snowpack depths at treeline range from 50-130 cm.
Weather Summary
Monday night
Partly cloudy, ridgetop wind 15 km/h southeast, treeline temperature -10 °C.
Tuesday
A mix of sun and cloud, ridgetop wind 15 km/h south, treeline temperature -7 °C.
Wednesday
Mostly cloudy, ridgetop wind <10 km/h south, treeline temperature -6 °C.
Thursday
A mix of sun and cloud, ridgetop wind <10 km/h south, treeline temperature -5 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Be mindful that deep instabilities are still present and have produced recent large avalanches.
- Uncertainty is best managed through conservative terrain choices at this time.
- Avoid shallow snowpack areas, rock outcroppings and steep convex terrain where triggering is most likely.
- Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
Problems
Persistent Slabs
A layer of surface hoar is buried 20-50 cm deep. If triggered, avalanches on this layer could step down to deeper weak layers.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
A layer of weak facets near the ground may be reactive to human triggering, especially in shallow, rocky areas in alpine terrain where the layer is not capped by a crust.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 2nd, 2024 4:00PM
