Avalanche Forecast

Issued: Feb 3rd, 2012 9:21AM

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

triley, Avalanche Canada

Sea To Sky.

Summary

Confidence

Good - -1

Weather Forecast

Warm daytime temperatures and freezing down to the valley bottoms is expected over the weekend. The freezing level is forecast to rise to about 2000 metres on both Saturday and Sunday. Expect mostly sunny skies and light south to southeast winds through the forecast period.

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

Cornices

New cornice growth may be easy to trigger due to rising temperatures and solar radiation. Cornice falls may trigger slabs on the slopes below.

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

Elevations: Alpine.

Likelihood

Likely - Very Likely

Expected Size

2 - 6

Storm Slabs

Steep solar aspects may be easily triggered or run naturally due to above freezing temperatures overnight combined with daytime heating. Avalanches may run full path and entrain moist snow in the track.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 6

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

Valid until: Feb 4th, 2012 3:00AM