Avalanche Forecast

Issued: Jan 7th, 2015 8:13AM

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

percy woods, Parks Canada

Glacier.

Over 70cm of storm snow along with 8-12hrs of moderate winds have formed storm slabs at and above treeline. Make conservative terrain choices.

Summary

Weather Forecast

Light winds, warming temperatures and a current temperature inversion will continue through today. A clearing trend is forecast for Friday with temperatures steady below zero.

Snowpack Summary

Over 70cm of storm snow, warming alpine temps and 8-12hrs of moderate S through SW winds make for building storm slabs and touchy conditions. The storm snow will be settling into a cohesive slab with a questionable bond to the old surface. The Dec 17th surface hoar layer, most prevalent at treeline elevations, may be reawakening with this load.

Avalanche Summary

Avalanche control yesterday produced numerous size 2 to 3.5 slides with most slides coming in at size 2.5. The larger slides were digging down to the Dec 17th layer. A natural avalanche cycle had occurred early in the morning of January 6th with slides up to 2.5 in size initiating in the storm snow at alpine elevations.

Confidence

Problems

Loose Dry

Sluffing can be expected in steeper features at and below treeline in non-wind affected locations. keep an eye out for people traveling below you in open terrain and stay out of terrain traps where sluffs can have larger consequences.

The new snow will require several days to settle and stabilize.Use caution above cliffs where small avalanches may have severe consequences.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Storm Slabs

The storm slab should be settling and stiffening with the warming temperatures. The question is the bond to the old snow surface of colder recrystalized snow. We currently think this interface is weak and ripe for triggering.

Use caution in lee areas. Recent wind loading have created wind slabs.Use conservative route selection, choose moderate angled and supported terrain with low consequence.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 3

Persistent Slabs

The December 17th layer produced our larger controlled slides yesterday. Slides initiating in the storm snow have a good probability of overloading this layer as they gain volume. This layer is most prevalent at treeline elevations.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Jan 8th, 2015 8:00AM