Avalanche Forecast

Issued: Apr 12th, 2017 4:09PM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs and Cornices.

jsmith, Avalanche Canada

Sea To Sky.

New snow and shifting wind directions may create wind slabs on a variety of aspects, including slopes that are generally windward.

Summary

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

THURSDAY: Cloudy with flurries (5-10 cm snow possible). Light to moderate Southwesterly ridgetop winds. Freezing level around 1200m.FRIDAY: Mostly cloudy. Light Southwesterly ridgetop winds. Freezing level around 1200 m.SATURDAY: Sunny. Light southwesterly ridgetop winds. Freezing level around 1400m.

Avalanche Summary

Numerous skier triggered size 1 wind slabs were reported at Treeline and above on a variety of aspects near Whistler on Wednesday.

Snowpack Summary

15 cm of new snow with moderate to strong winds from a variety of directions have created fresh wind slabs in exposed terrain at treeline and above. Numerous crusts exist in the upper snowpack, especially on solar aspects. Cornices are large and remain a concern: Saturday's fatal accident near Lions Bay illustrates the danger of them breaking off, and the large avalanches they can trigger. Expect small loose dry avalanches in steep terrain where the new snow is sitting on a crust.

Problems

Wind Slabs

Shifting wind directions have created fresh wind slabs on a variety of aspects.

Pay attention to changing conditions with elevation.Use ridges or ribs to avoid pockets of wind loaded snow.Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Cornices

Recent snow and wind are growing already large cornices. Minimize your exposure to cornices when it is cold and cloudy and completely avoid them when it is warm and/or sunny.

Extra caution needed around cornices with current conditions.Give cornices a wide berth when travelling on or below ridges.Falling cornices can trigger large avalanches.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Apr 13th, 2017 2:00PM