Archived

Avalanche Forecast

Apr 14th, 2017–Apr 15th, 2017

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

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

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.

The key weather factors to keep your eye on this weekend will be the sunshine accompanied by rising freezing levels. Solar radiation is a common trigger for cornices which is currently our primary concern.

Confidence

High -

Weather Forecast

SATURDAY: Mix of sun and cloud. Light westerly ridgetop winds. Freezing level around 1500m.SUNDAY: Sunny. Light southwesterly ridgetop winds. Freezing level rising to around 1800m.MONDAY: Mix of sun and cloud. Light southwesterly ridgetop winds. Freezing level hovering around 1700m.

Avalanche Summary

Two size 3.5 deep persistent slab avalanches were reported on Wednesday with crowns up to 4 metres deep. One was triggerd by a cornice and the other by solar radiation. The key weather factor to keep your eye on this weekend will be the sunshine accompanied by rising freezing levels. Solar radiation is a common trigger for cornices which is currently our primary concern.

Snowpack Summary

Recent snow and wind have formed wind slabs in the alpine on a variety of aspects caused by shifting wind directions. Cornices are large, looming, and the primary concern due to their potential to trigger large avalanches failing on facets at the bottom of the snowpack.

Avalanche Problems

Cornices

Minimize exposure to slopes with large cornices overhead when it is cool and cloudy and completely avoid them if it is warm and/or sunny.

Give cornices a wide berth when travelling on or below ridges.Cornice failures could trigger large avalanches.

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

Elevations: Alpine.

Likelihood: Unlikely - Possible

Expected Size: 2 - 3

Wind Slabs

Lingering wind slabs may still be reactive to human triggers in isolated locations.

Keep an eye out for reverse loading created by shifting winds.Use ridges or ribs to avoid pockets of wind loaded snow.Be cautious with wind loaded pockets near ridge crests and roll-overs.

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 1 - 2