Avalanche Forecast

Issued: Dec 16th, 2015 7:59AM

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

triley, Avalanche Canada

Sea To Sky.

Cloud developing during the day with some wind and snow by afternoon will increase wind slab danger in the alpine and at treeline.

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain on Friday

Weather Forecast

Cloud developing Thursday morning as southerly winds push the next storm into the region. Expect 3-5 cm during the day and another 10-20 cm by Friday morning combined with moderate southwest winds. Light snow and westerly winds on Friday with the freezing level rising up to 700 metres. The next storm should develop on Saturday night.

Avalanche Summary

No new natural avalanches reported. Some explosive controlled cornice was reported up to size 2.0 on Tuesday.

Snowpack Summary

On Tuesday, 5-10cm of low-density snow was redistributed by winds into new wind slabs at treeline and in the alpine. These new wind slabs overlie 40-50cm of storm snow from last weekend. Limited observations suggest the recent storm snow has gained considerable strength, although I'd continue to be wary of lingering pockets of wind slab on high elevation, wind-loaded slopes. On steep, south-facing terrain you may find a sun crust from solar warming on Monday. Below 2200m, a hard rain crust can be found approximately 120cm below the surface.

Problems

Wind Slabs

Some pockets of windslab may continue to be triggered by light additional loads in the alpine and at treeline.

Be alert to conditions that change with elevation.>Be cautious as you transition into wind affected terrain.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Cornices

Cornices may be weak with new growth and may fall off naturally or with continued wind loading.

Extra caution needed around cornices with current conditions.>Stay well back from cornices.>

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Dec 17th, 2015 2:00PM