Archived

Avalanche Forecast

Feb 22nd, 2016–Feb 23rd, 2016

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

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

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: Sea To Sky.

Avalanches will be more likely on slopes that see direct sun on Tuesday.

Confidence

High - Due to the number and quality of field observations

Weather Forecast

TUESDAY: sunny, light southeasterly winds, 1500m freezing level. WEDNESDAY: partly cloudy with flurries possible, light southwesterly winds, 1500m freezing level. THURSDAY: mainly sunny, light southwest winds, freezing level rising to 3000m.

Avalanche Summary

Numerous natural and artificially triggered storm slab avalanches were reported over the weekend. Although natural avalanche activity is now slowing, wind slab avalanches are expected to remain reactive to human-triggering. Cornices are reported to be large and fragile, and may fail under the weight of a person.

Snowpack Summary

The recent storm snow continues to settle and gain strength, however, some lingering mid storm instabilities are still reactive to ski cutting in steeper terrain features. Ongoing southeast through southwest winds have been loading lee features in the alpine and at treeline and cornices are large and fragile. A thin breakable crust may cap moist snow on slopes that see direct sun. Several crusts can be found in the upper meter depending on elevation and aspect. The upper snow pack is sitting on a more widespread and thicker crust that extends into the alpine. In most places this crust is bridging a layer of surface hoar buried in early January. It is becoming increasingly hard to make this layer fail in snowpack tests and triggering an avalanche on it is unlikely.

Avalanche Problems

Storm Slabs

The recent storm slabs continue to be reactive to human triggering especially on wind loaded slopes. If the sun shines it may have enough punch to trigger natural avalanches.

Avoid freshly wind loaded features.>Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 3

Cornices

Cornices are reported to be large and weak. The weight of a person may be enough to cause a cornice failure.

Pay attention to overhead hazards like cornices.>Give cornices a wide berth when travelling on or below ridges.>

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

Elevations: Alpine.

Likelihood: Unlikely - Possible

Expected Size: 1 - 4