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Avalanche Forecast

Jan 19th, 2023–Jan 20th, 2023
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
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
3: Considerable
The avalanche danger rating at treeline will be considerable
Below Treeline
2: Moderate
The avalanche danger rating below treeline will be moderate
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
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: East Island, North Island, South Island, Vancouver Island, West Island.

Assess for wind slabs in steep terrain near ridges.

Confidence

Moderate

Avalanche Summary

Wind slabs were triggerable by riders on Thursday at higher elevations. On Wednesday, many small to large (size 1 to 2) storm slab and dry loose avalanches were triggered by riders and naturally within the 30 to 60 cm of snow from Tuesday night.

Looking ahead, riders could trigger wind slabs in lee terrain features where wind has redistributed the storm snow. It also remains possible that riders could trigger storm slabs in sheltered areas, particularly if all the recent storm snow has a poor bond to the underlying melt-freeze crust.

Snowpack Summary

Around 5 to 15 cm of snow is forecast to accumulate by Friday afternoon along with southwest wind. This snow builds on the 30 to 60 cm of snow that accumulated Tuesday night with strong wind. Wind slabs are found near ridges in wind-exposed terrain. All this snow is consolidating in areas sheltered from the wind, which may take a bit of time to bond to a hard melt-freeze crust found below 1500 m.

Snowpack depths at treeline are around 100 cm, tapering quickly with elevation. Although the snowpack in most forested areas below treeline remains below threshold depths for avalanches, many steep bluffs, cut-banks, and alpine-like features in the upper below treeline band are capable of producing avalanches.

Weather Summary

Thursday Night

Cloudy with snowfall, accumulation 5 to 10 cm, 30 km/h southwest wind, treeline temperature -3 °C, freezing level 800 m.

Friday

Cloudy with snowfall, accumulation 2 to 5 cm, 20 to 30 km/h west wind, treeline temperature -1 °C, freezing level rising to 1300 m.

Saturday

Cloudy with snowfall then clearing, accumulation 15 to 25 cm, 80 km/h southwest wind, treeline temperature -1 °C.

Sunday

Mix of sun and cloud with no precipitation, 30 km/h northwest wind, treeline temperature -2 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • 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.
  • Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.

Avalanche Problems

Wind Slabs

Wind slabs have formed in lee terrain features from all the recent snow. Assess for slabs prior to committing to large terrain. Also use caution in steep wind-sheltered terrain, where the recent snow may take a bit of time to bond to an underlying crust.

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2