Avalanche Forecast

Issued: Feb 2nd, 2012 9:28AM

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

triley, Avalanche Canada

Sea To Sky.

Summary

Confidence

Good - -1

Weather Forecast

There is a band of warm air at higher elevations that may keep temperatures in the alpine quite warm overnight; probably about -3.0 at 2500 metres. Clear skies should allow the valleys to get slightly below freezing. Friday is expected to be warm with light southerly winds and mostly sunny skies. Temperatures should drop to near freezing in the valley bottoms overnight. Light upslope precipitation is expected to bring trace amounts of snow on Saturday. Sunday is expected to be mostly clear with light winds and freezing levels up to about 1200 metres.

Avalanche Summary

Some sloughing from steep shaded aspects in the alpine to size 1.0. Also, moist surface snow releases up to size 1.0 on solar aspects.

Snowpack Summary

Recent strong southerly winds have created soft windslabs in the alpine and at treeline that are settling and bonding due to the warm temperatures. Pockets of dry snow in the alpine may become active with the initial warming. Some sun crust is developing on steep solar aspects. Shallow rocky areas continue to be a concern due to the formation of weak buried facets. Surface instabilities, cornice releases, or other large loads may trigger deep buried weak layers; this is a low probability, high consequence situation.

Problems

Wind Slabs

Warm temperatures are expected to continue to settle and bond recent windslabs in the alpine and at treeline. Some pockets of dry snow on shaded slopes may be reactive as freezing levels rise.

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 4

Storm Slabs

Storm slabs are expected to gain strength and continue to bond to the old surface.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

1 - 4

Cornices

New cornice growth may be easy to trigger due to rising temperatures and solar radiation.

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

Elevations: Alpine.

Likelihood

Likely

Expected Size

2 - 5

Valid until: Feb 3rd, 2012 3:00AM