Avalanche Forecast
Issued: Apr 21st, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Cornices.
TRettie,
Avalanche Canada
Carefully assess new snow amounts. The size and likelihood of wind slab avalanches will be greatest in localized areas that receive more than 15 cm of new snow.
Summary
Confidence
Weather Forecast
Thursday night: around 10 cm of new snow expected with localized areas in the north receiving up to 20 cm of new snow. Light to moderate west winds. Low of -4 at 2000 m.
Friday: A mix of sun and cloud with the possibility of light flurries bringing trace amounts of new snow. Light northwest winds and freezing levels rising to 2000 m.
Saturday: A mix of sun and cloud with the possibility of light flurries bringing trace amounts of snow. Light variable winds and freezing levels rising to 2300 m.
Sunday: A mix of sun and cloud with no new snow expected. Light south winds and freezing levels around 2300 m.
Avalanche Summary
On Wednesday several natural wind slab avalanches up to size 2.5 were observed in the region. Small wet loose avalanches were also observed on solar aspects.
We suspect that rider triggerable wind slab will still be found in exposed treeline and alpine terrain.
Snowpack Summary
On north aspects above 2000 m Around 30 cm of recent storm snow overlies a variety of old surfaces including wind effect and facets. Several crusts exist on solar aspects extending to mountain tops.
Cornices are very large and exposure to slopes beneath them should be minimized, especially if the weather is sunny, warm, or windy. The snowpack deteriorates rapidly at lower elevations.
Terrain and Travel
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Closely monitor how the new snow is bonding to the crust.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Problems
Wind Slabs
Winds have varied in direction over the past few days. look for wind slab on all aspects.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Cornices
Cornices may be weak and reactive to human triggers. Give them a wide berth when travelling on ridges. They are a significant hazard alone and may produce large slab avalanches as they fall onto the slope below. Cornice falls are more likely when the weather is sunny, warm, or windy.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 22nd, 2022 4:00PM
