Avalanche Forecast

Issued: Mar 2nd, 2016 4:00PM

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.

Max Darrah, Parks Canada

Jasper.

Several reports of skier triggered avalanches in the alpine on wind loaded features. Be cautious of recently opened areas of the park that have not seen skier traffic.

Summary

Weather Forecast

Tuesday night may bring 5-10cm of new snow and light South winds. Wednesday-Thursday will be -2 to -10, light flurries, and 1400-1700m freezing level. Thursday-Friday will warm up with increasingly strong Westerly winds.

Snowpack Summary

Weak crust on S through W aspects. Dry, facetted and generally unsupportive facets below this crust. 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. The Jan 28 SH/FC layer down 80cm remains a concern but is sporadically distributed.

Avalanche Summary

Loose dry sluffing from all aspects in the ALP out of steep rocky terrain up to sz 1. Several reports of remotely triggered slab avalanches in the alpine in wind loaded areas up to size 2. These slides went on old snow and are especially prevalent in areas that have not seen skier traffic this winter.

Confidence

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 and release to ground.

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

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - 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.

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

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Mar 3rd, 2016 4:00PM