Avalanche Forecast
Issued: Mar 13th, 2024 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
jleblanc,
Avalanche Canada
Persistent slabs remain prime for human-triggered avalanches, especially at treeline.
The likelihood of triggering will increase with each day of warm weather.
Summary
Confidence
Moderate
Avalanche Summary
On Tuesday, large persistent slab and wind slab avalanches (up to size 2.5) occurred naturally on east slopes at treeline and alpine, respectively. Whumpfs and shooting cracks were also observed at treeline. Large avalanches continue to surprise skiers across the region, with several remotely triggered from a distance from low-angle or flat terrain.
For more information, click on the photos below.
Snowpack Summary
Expect to find up to 25 cm of settled snow in wind-sheltered and shady areas. This snow covers wind-affected surfaces or a crust on sun-exposed slopes and at lower elevations. A layer of weak, faceted crystals over a crust, or surface hoar, is the primary layer of concern, buried around 40 to 80 cm.
A sun crust may have formed on the surface on steep south and west-facing slopes, and snow will be heavier and possibly moist or crusty at lower elevations.
Weather Summary
Wednesday Night
Cloudy with 2 to 4 cm of new snow expected. 50 to 60 km/h southwest ridgetop wind. Treeline temperatures around 0 °C. Freezing level around 1000 m.
Thursday
Cloudy with 2 to 4 cm of new snow expected. 50 to 70 km/h southwest ridgetop wind. Treeline temperatures around +2 °C. Freezing level rising to 1800 m.
Friday
Mainly cloudy with no precipitation, 30 to 40 km/h southwest ridgetop wind. Treeline temperatures around +5 °C. Freezing level rising to 2200 m.
Saturday
Mainly cloudy with no precipitation, 30 to 40 km/h southwest ridgetop wind. Treeline temperatures around +9 °C. Freezing level rising to 3500 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Remote triggering is a concern, watch out for adjacent and overhead slopes.
- Approach steep open slopes at and below treeline cautiously, buried surface hoar may exist.
- Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
Problems
Persistent Slabs
Several recent avalanches in the region continue to be triggered on a layer of buried surface hoar or weak, sugary facets overlying a crust. Use caution in shallow areas where triggering these avalanches is most likely.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
Steady strong wind will continue to develop fresh, reactive slabs in leeward terrain. If triggered, wind slab avalanches may step down to deeper layers resulting in larger-than-expected avalanches.
Aspects: North, North East, East, West, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 14th, 2024 4:00PM
