Avalanche Forecast

Issued: Jan 25th, 2012 9:28AM

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

Avalanche Canada triley, Avalanche Canada

Summary

Confidence

Fair - Forecast snowfall amounts are uncertain on Thursday

Weather Forecast

Strong southwest winds are expected to swing more westerly by Thursday morning. Moderate precipitation should continue overnight Wednesday and during the day Thursday bringing another 15 cm to treeline elevations by Thursday morning. A further 15 cm of snow at treeline during the day on Thursday is forecast to be combined with very strong and gusty westerly winds. A weak ridge of high pressure should develop briefly on Friday. The wind should drop a bit, but still be about 40-60 km/hr from the west with flurries. The next Pacific system should move in from the coast overnight or early Saturday morning. This system is still a few days away, but is forecast to combine very strong southwest winds, heavy precipitation, and freezing levels rising to about 1000 metres.

Avalanche Summary

Debris observed from natural avalanches up to size 3.0. I suspect that there has been a widespread natural avalanche cycle.

Snowpack Summary

The storm continues to bring heavy snowfall and strong southwest winds. Conditions are building new windslabs and storm slabs above the recent storm snow that has consolidated into a slab. The old windslabs are on south through west aspects, and they are stiff and continue to be easily triggered. New windslabs are building on north through east aspects, making travel a bit tricky; limited options exist for avoiding both types of windslab. The deep snowpack is considered to be well settled with no persistent layers of concern.

Problems

Wind Slabs

An icon showing Wind Slabs
The new storm is expected to continue to build windslabs in the alpine and at treeline due to very strong southwest winds and heavy precipitation. Watch for re-loading as the storm continues.

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

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

3 - 6

Storm Slabs

An icon showing Storm Slabs
The new storm will add to the storm slab that is sitting above a weak layer that developed during the recent cold weather. Forecast warm temperatures may consolidate this blanket of snow into a cohesive slab that is easily triggered.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

3 - 7

Valid until: Jan 26th, 2012 8:00AM