Avalanche Forecast

Issued: Dec 7th, 2017 4:00PM

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

a.l. horton, Parks Canada

Jasper.

Good skiing can be found on north aspects. Solar triggering is possible on all steep south aspects in the Alpine. Ice climbers take heed.

Summary

Weather Forecast

Continued warm temperatures at treeline and above with sunny skies and light NW winds as the inversion continues through Friday. A gradually cooling trend into the weekend is forecast as the warm air mixes and descends to the valley bottom.

Snowpack Summary

There is a well settled snowpack in most locations. A 30 - 70 cm persistent slab overlies a significant crust (Nov.23). Bonding appears to be strengthening at this interface. The Halloween crust sits near the bottom of the snowpack from treeline to 2700 m.

Avalanche Summary

There were numerous dry loose avalanches (size 1-2), along the Icefields Parkway and Maligne Lake Road on steep solar aspects, running to treeline today. A large size 3 slab avalanche was observed in the Icefields this afternoon on a steep South facing slope that ran on the Halloween Crust to treeline.

Confidence

The weather pattern is stable on Friday

Problems

Loose Dry

Solar triggering of loose dry avalanches is occurring in steep terrain. The entraining snow may have the volume to knock ice climbers off their stances.

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Deep Persistent Slabs

Solar triggering is possible on steep south facing slopes creating large full path avalanches.

Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 3

Valid until: Dec 8th, 2017 4:00PM