Avalanche Forecast

Issued: Dec 18th, 2015 4:00PM

The alpine rating is low, the treeline rating is low, and the below treeline rating is low. Known problems include Wind Slabs and Persistent Slabs.

rupert wedgwood, Parks Canada

Jasper.

Take a progressively incremental approach to committing terrain features in this time of low avalanche danger and be prepared to scale back if signs indicating more dangerous conditions.

Summary

Weather Forecast

The winds are forecast to increase to strong from the SW. The overnight temps at alpine elevations will be around -10 with daytime highs of -5. Up to 10cm of new snow may fall over the weekend at higher elevations but no significant storms are forecast. Increased winds will build soft slabs in the alpine terrain.

Snowpack Summary

A dusting of new snow in past 12 hr . Above 2000m the meter deep snowpack is very supportive . A weak surface hoar layer, buried on Dec 3rd, lurks below 45-60cm of snow. This layer is of concern at and below treeline on northerly facing slopes. In the Alpine thin wind slabs can be found above 2,800m. Below 1,700m the snowpack is weak and shallow.

Avalanche Summary

No new avalanche activity observed and reported

Confidence

Forecast snowfall amounts are uncertain on Monday

Problems

Wind Slabs

New (and previously) building windslab will be found in lee areas at treeline and into the alpine.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Avoid shallow snowpack areas where triggering is more likely.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

The Dec3 layer down 60cm has not been associated with any observed natural activity nor has it proven to be reactive to skier traffic. Further cooling temperatures and the consistently supportive mid-pack helping increase confidence in this layer.

Carefully evaluate big terrain features by digging and testing on adjacent, safe slopes.Be cautious of buried obstacles in shallow snowpack areas.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

1 - 2

Valid until: Dec 19th, 2015 4:00PM