Archived

Avalanche Forecast

Apr 20th, 2022–Apr 21st, 2022

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: North Columbia.

Continue to assess the wind slab hazard as you gain elevation.

Confidence

Moderate - The snowpack structure is generally well understood.

Weather Forecast

Wednesday night: No new snow expected. Light southeast winds and a low of -8 at 2000 m.

THURSDAY: Mostly cloudy with flurries bringing trace amounts of new snow with light southeast winds. Freezing level rising to 1900 m.

Friday: Mostly cloudy with flurries bringing up to 10 cm of new snow with light northwest winds. Freezing level around 2000 m.

Saturday: Sunny with no new snow expected. Light northwest winds and freezing levels rising to 2200 m.

Avalanche Summary

On Tuesday skier traffic produced numerous size one storm and wind slab avalanches at treeline and above.

We suspect that small wind slab avalanches will remain possible.Â

Snowpack Summary

15 to 30 cm of new snow overlies a variety of surfaces including old wind effected surfaces, facets and a crust on solar aspects. Below this another melt-freeze crust can be found down 20 to 50 cm on all aspects to 2000 m and mountain tops on solar aspects.Â

The late March crust layer is found 40 to 90 cm deep.

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.

Avalanche Problems

Wind Slabs

New wind slabs will likely be found in exposed treeline and alpine terrain. These new slabs likely won't bond well to the underlying surfaces.

Aspects: North, North East, East, South East, West, North West.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2

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: Unlikely

Expected Size: 1.5 - 3