Avalanche Forecast

Issued: Dec 19th, 2015 7:32AM

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

Avalanche Canada triley, Avalanche Canada

Continued stormy weather will trend the avalanche danger up over the weekend. If your area gets more snow than forecast, then these danger ratings may be a bit low.

Summary

Confidence

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

Weather Forecast

5-10 cm overnight with very strong southwest winds and freezing levels around 500 metres. Another 5-15 cm during the day Sunday with slightly lower wind values expected. Snowfall amounts may be locally higher in the south of the region around Manning Park and the Coquihalla. Continued light snow on Monday with moderate southwest winds and a chance of the freezing level rising up to about 800 metres. More light snow, cool temperatures, and increasing winds on Tuesday.

Avalanche Summary

Soft windslabs released naturally or were triggered by fresh cornice falls in the Duffy Lake area on Friday up to size 2.0

Snowpack Summary

Less new snow in the Duffy Lake area; 10 cm new on Friday with strong alpine winds building windslabs and cornices. There was 15-20 cm of new snow on Friday morning available to be transported into windslabs by moderate southerly winds. These new storm and wind slabs may be sitting on a new layer of surface hoar that was buried on Thursday. The new storm snow is above 40-50 cm of snow from last week, that may also be sitting on a buried surface hoar layer. There is about 100 cm of settled snow above the December 8th melt-freeze crust. There is about 200 cm at 1800 metres in the Coquihalla.

Problems

Storm Slabs

An icon showing Storm Slabs
New snow will add to the existing storm slabs. Strong winds at higher elevations are expected to create deep pockets of wind transported snow. Cold temperatures may limit slab development.
Avoid avalanche terrain during periods of heavy loading from new snow and wind.>Avoid travelling in areas that have been reverse loaded by winds.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 3

Cornices

An icon showing Cornices
New cornice growth may be weak and fall off naturally or be triggered by continued loading from new snow and wind.
Extra caution needed around cornices with current conditions.>Give cornices a wide berth when travelling on or below ridges.>

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Dec 20th, 2015 2:00PM