Avalanche Forecast
Issued: Jan 6th, 2024 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs, Wind Slabs and Deep Persistent Slabs.
wlewis,
Avalanche Canada
Avoid areas where the snowpack is thin and rocky. Weak layers are most triggerable here.
Summary
Confidence
Avalanche Summary
Explosive control work over the past week has triggered large avalanches on buried weak layers. This includes reloaded bed surfaces of previous avalanches (where the snowpack becomes more faceted and weaker).
Last weekend, a skier in the Dogtooth Range accidentally triggered a size 2 deep persistent slab on basal facets over a smooth rock slab.
While avalanche activity has decreased these layers remain possible for human triggering with high consequences.
Snowpack Summary
New snow continues to gradually accumulate over old surfaces including crusts, facets and surface hoar. Beneath lies a complex snowpack with several layers of concern.
A layer of surface hoar is buried 40 to 70 cm deep. It is a concern at elevations (generally above 2000 m) where it is not bridged by a hard crust above.
Weak basal facets characterize the lower snowpack, especially in alpine terrain.
Read this blog post for more details.
Snowpack depths at treeline range from 60 to 130 cm.
Weather Summary
Saturday Night
Mostly cloudy with 5-10 cm of snow. Freezing levels at valley bottom. Light and variable winds.
Sunday
Mostly cloudy with a possible afternoon sun. Northwest winds, 10-20 km/h. Freezing levels at valley bottom. Treeline temperature -8 °C.
Monday
Partly cloudy, westerly winds 20-30 km/h. Freezing levels at valley bottom, treeline temperature -12 °C.
Tuesday
Partly cloudy, southwest winds 20-50 km/h. Freezing levels at valley bottom, treeline temperature -7 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Uncertainty is best managed through conservative terrain choices at this time.
- Be mindful that deep instabilities are still present and have produced recent large avalanches.
- Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
- Closely monitor how the new snow is bonding to the old surface.
Problems
Persistent Slabs
Buried surface hoar is likely becoming harder to trigger. However, consequences remain high if triggered. Small avalanches have potential to step down to deeper layers.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Wind Slabs
Fresh snow and winds have likely built small but reactive wind slabs.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
A layer of weak facets near the ground can be triggered by large loads or even by riders in shallow rocky areas.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Jan 7th, 2024 4:00PM
