Avalanche Forecast
Issued: Feb 28th, 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.
mbender,
Avalanche Canada
More snow and wind arriving Wednesday night means avalanche danger will remain High. Persistent slab avalanches are primed for rider triggering.
Summary
Confidence
Moderate
Avalanche Summary
Numerous natural and rider triggered storm slab and persistent slab avalanches size 1 to 3 have been reported the past few days in the alpine and treeline elevation bands on all aspects. Most of these occurred on the weak layer of faceted grains 60-100 cm deep sitting on a crust formed in early February. Several were reported as remotely triggered (from a distance).
Expect rider triggered avalanches to be likely as more snow and wind arrives Thursday night.
Snowpack Summary
70 to 110 cm of recent snow sits on a variety of layers that it may not bond well to, including surface hoar in wind-sheltered terrain, weak facets, or a hard melt-freeze crust on sun-exposed south and west-facing slopes. The wind has likely formed thicker deposits in lee terrain features near ridges.
A thick and hard widespread crust that formed in early February is buried 50 to 100 cm deep and is found up to around 2400 m. This crust may have a layer of facets above it, which makes it a troublesome avalanche layer.
The remainder of the snowpack is settled.
Weather Summary
Wednesday Night
Cloudy with 10 to 20 cm of snow. 30 to 60 km/h southwest ridgetop wind. Treeline temperature -5 °C. Freezing level 1000 m.
Thursday
Cloudy with 5 to 15 cm of snow. 20 to 40 km/h southwest ridgetop wind. Treeline temperature -7 °C. Freezing level at valley bottom.
Friday
Mostly cloudy with sunny breaks and 1 to 3 cm of snow. 15 to 25 km/h southwest ridgetop wind. Treeline temperature -7 °C.
Saturday
A mix of sun and cloud, 15 to 25 km/h southeast, Treeline temperature -8 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Only the most simple non-avalanche terrain free of overhead hazard is appropriate at this time.
- Shooting cracks, whumphs and recent avalanches are strong indicators of an unstable snowpack.
- Fresh snow rests on a problematic persistent slab, don't let good riding lure you into complacency.
- Storm slabs in motion may step down to deeper layers resulting in large avalanches.
Problems
Storm Slabs
Storm slabs are likely to remain reactive to human traffic, particularly where they sit on problematic weak layers or hard surfaces. Giving the snow time to heal is warranted at this time.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
A weak layer of faceted grains above a melt-freeze crust buried 50 to 100 cm deep is a recipe for large, high-consequence avalanches. This snowpack setup will take some time to strengthen.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 29th, 2024 4:00PM
