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Avalanche Forecast

Feb 26th, 2020–Feb 28th, 2020
Alpine
4: High
The avalanche danger rating in the alpine will be high
Treeline
3: Considerable
The avalanche danger rating at treeline will be considerable
Below Treeline
Below Threshold
The avalanche danger rating below treeline will be below threshold
Alpine
4: High
The avalanche danger rating in the alpine will be high
Treeline
3: Considerable
The avalanche danger rating at treeline will be considerable
Below Treeline
Below Threshold
The avalanche danger rating below treeline will be below threshold
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
Below Threshold
The avalanche danger rating below treeline will be below threshold

Regions: Yukon.

Minimize exposure to avalanche terrain as a series of storms are creating dangerous avalanche conditions.

Confidence

High - We are confident the likelihood of avalanche will increase with the arrival of the forecast weather.

Weather Forecast

A series of frontal systems will bring steady snowfall and strong wind for the remainder of the week.

WEDNESDAY NIGHT: 5-10 cm of new snow, 40-60 km/h wind from the southwest, alpine temperatures around -10 C.

THURSDAY: Steady snowfall with 10-20 cm of new snow, strong wind from the south, alpine high temperatures around -5 C.

FRIDAY: Steady snowfall continues with another 10-20 cm of snow, moderate to strong wind from the west, alpine high temperatures around -7 C.

SATURDAY: Mix of sun and cloud, moderate southwest wind, alpine high temperatures around -10 C.

Avalanche Summary

The primary concern this week will be new slabs forming as snow accumulates.

No notable avalanches have been reported since Saturday when a large (size 3) avalanche was observed on a very steep north alpine face in Taiya Valley. It was triggered by a collapsing cornice which is a good reminder to minimize your exposure to slopes with cornices overhead.

Snowpack Summary

New slabs will form this week as the weather forecast calls for roughly 10-20 cm of snow per day with strong south wind. Old wind slabs can be felt on a variety of aspects beneath the new snow, and thin sun crusts have been reported on south-facing slopes. Cornices are reported to be growing in size as well.

At White Pass the snowpack is roughly 200 cm thick and well-bonded, while in the Wheaton Valley the snowpack is much thinner and capped by a breakable crust.

Terrain and Travel

  • Minimize exposure during periods of heavy loading from new snow and wind.
  • Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.
  • Seek out sheltered terrain where new snow hasn't been wind-affected.

Avalanche Problems

Wind Slabs

Thick and dangerous wind slabs are forming as a series of storms hit White Pass. Natural avalanches are likely in alpine terrain during intense periods of the storm. There looks to be a break in the storm on Saturday, but human triggered wind slab avalanches will remain likely.

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

Elevations: Alpine, Treeline.

Likelihood: Likely - Very Likely

Expected Size: 1 - 2.5