Avalanche Forecast

Issued: Dec 21st, 2014 4:00PM

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

a.l. horton, Parks Canada

Jasper.

Excellent skiing reported around Hilda Ridge today. The avalanche hazard will increase on Tuesday as a storm will hit with heavy snow and strong West winds.

Summary

Weather Forecast

Continued snow flurries with moderate W winds on Monday. Snow begins on Tuesday afternoon intensifying through the night and then tapering by Wednesday afternoon with up to 20 cm expected. Strong westerly winds will accompany this storm. Seasonal temperatures that will fall after the storm has past.

Snowpack Summary

Wind slab forming on lee alpine ridge lines. Large surface hoar crystals formed last week are being buried by new snow. This layer is more likely found on sheltered slopes at tree line reaching into the alpine. The interface between the strong mid-pack and weaker basal facets is most susceptible to human triggering from shallow rocky areas.

Avalanche Summary

Some minor loose snow sluffing on steep terrain. No slab avalanches reported today.

Confidence

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

Problems

Wind Slabs

Wind loading producing wind slabs on lee and cross loaded features predominately below alpine ridge lines.

Be cautious as you transition into wind affected terrain.Be careful with wind loaded pockets while approaching and climbing ice routes.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Deep Persistent Slabs

This layer can be found above 1900m and can be triggered from shallow areas in the snowpack. A strong rain crust exists below tree line up to 1900m.

Carefully evaluate and use caution around thin snowpack areas.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Dec 22nd, 2014 4:00PM