Avalanche Forecast

Issued: Dec 19th, 2012 8:50AM

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

Avalanche Canada ghelgeson, Avalanche Canada

Summary

Confidence

Fair - Due to limited field observations

Weather Forecast

Wednesday night:  Strong to Extreme SW winds at ridgetop.Thursday: Strong to Extreme SW winds at ridgetop.  1500m temp -10. Light to moderate snowfall resulting in 5 - 15 cm of snow.Friday: Light to Moderate SW winds at ridgetop.  1500m temp -15.  Clearing skies.Saturday:  Variable southerly winds at ridgetop.  1500m temp -15. Occasional flurries.

Avalanche Summary

No new avalanche observations.  Observations are welcome, please email us: forecaster@avalanche.ca

Snowpack Summary

The upper snowpack comprises deep amounts of unconsolidated snow in sheltered locations, and soft slabs in open, exposed locations. These slabs are most likely immediately behind ridge crests and downslope ribs. There's ample recent snow available to fuel slab development if winds pick up. Overall, the top and mid-snowpack is reported to be settling well. Persistent and Deep persistent instabilities (surface hoar and an early November crust, respectively) located in the middle and near the bottom of the snowpack may still be a concern but there's little recent evidence of them. It is important to know that we have very limited observations for this region. Digging down and making your own observations, especially in thinner snowpack areas, remains a good idea to assist safe slope selection. You're looking for weak layers that pop or drop in stability tests.

Problems

Wind Slabs

An icon showing Wind Slabs
Wednesday evening is a bit of "game changer" as SW winds amp up to extreme values and begin to form sensitive wind slabs. There is potential for large human triggered avalanches in wind exposed features.
Conditions are changing and you need to adapt your plans accordingly. Avoid wind exposed terrain at and above treeline.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

2 - 6

Valid until: Dec 20th, 2012 2:00PM