Avalanche Forecast

Issued: Feb 28th, 2016 4:27PM

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

a.l. horton, Parks Canada

Jasper.

Heads up!! Conditions are ripe even though we are not seeing a lot of natural activity. Stick to sheltered low angle slopes.

Summary

Weather Forecast

Seasonable temps into Monday with 10 cm of snow overnight. SW winds predicted to be light.Â Temps cooling on Tuesday and a bit more snow expected on Wednesday.Â Max freezing level 1500 m for the next few days with mostly cloudy skies.

Snowpack Summary

Recent sun has developed a weak crust on S through W aspects. Dry, facetted and generally unsupportive facets below this crust.Â Wind slab on lee aspects from previous SW winds and persistent slab in open areas at tree line. Poor travel conditions below tree line due to weak facetted snowpack.

Avalanche Summary

Size 3 skier triggered avalanche on a SW facing alpine slope up Portal Creek today indicates that the persistent slab can be triggered.

Confidence

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

Problems

Persistent Slabs

Persistent weak layers of decomposed surface hoar, facets, and depth hoar are in many locations. These layers have been stubborn to trigger underfoot but could be triggered by cornice failure or from shallow spot.

Carefully evaluate terrain features by digging and testing on adjacent, safe slopes. Avoid steep slopes below cornices.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Wind Slabs

Expect slab development immediate to lee ridge lines and cross loaded features. Bonding should be suspect, progress cautiously into steeper terrain.

Carefully evaluate terrain features by digging and testing on adjacent, safe slopes. Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Feb 29th, 2016 4:00PM