Avalanche Forecast

Issued: Dec 16th, 2012 8:38AM

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

Avalanche Canada istorm, Avalanche Canada

Summary

Confidence

Fair - Timing, track, or intensity of incoming weather is uncertain on Monday

Weather Forecast

Synopsis: The storm track is along the USA border so Monday's storm will bring mostly wind to the region with little new snow. Tuesday looks quiet before the next system on Wednesday or Thursday.Monday:  Mod to Strong South or SW winds; 5 to 15 cm of snow; continued cool with alpine temperatures near -10CTuesday: Light NW wind; dry; colder with alpine temperatures around -14CWednesday: Light S wind; little if any snow; continued cool.

Avalanche Summary

Mostly small loose snow avalanches from steep terrain were reported for this region but visibility was limited and some of our regular reporters weren't able to get out yesterday. Due to our limited observations for this region at this time, your avalanche observations are welcome at forecaster@avalanche.ca

Snowpack Summary

Windslabs were developing Saturday afternoon and this process should continue Sunday & Monday in the alpine and treeline elevations with forecast S or SW winds. These slabs are most likely immediately behind ridge crests and downslope ribs. There's ample recent snow available to fuel slab development as winds pick up. Overall, the top and mid-snowpack is reported to be settling well. Deep persistent instabilities (surface hoar and early November crust) 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. Any observations from the field are welcome at forecaster@avalanche.ca.

Problems

Wind Slabs

An icon showing Wind Slabs
Expect growing windslabs in exposed lee slopes and cross-loaded gullies below ridge crests.
Assess start zones carefully and use safe travel techniques.>Use ridges or ribs to avoid pockets of wind loaded snow.>Whumpfing, shooting cracks and recent avalanches are all strong indicators of an unstable snowpack.>Watch for whumpfing, hollow sounds, shooting cracks or recent avalanches.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 4

Valid until: Dec 17th, 2012 2:00PM