Avalanche Forecast

Issued: Nov 11th, 2019 4:00PM

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

Parks Canada Conrad Janzen, Parks Canada

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Watch for new wind slabs in steep alpine terrain as the winds pick up Monday night and into Tuesday.

Good skiing can be found in sheltered areas with the normal cautions for early season hazards and a thin snowpack.

Summary

Weather Forecast

Some gusty West winds are expected Monday night and into Tuesday easing up by the end of the day. A few cm's of snow is also expected but accumulations will be minimal. Temperatures will be in the -2 to -6 range at treeline.  Wednesday and Thursday look cool and clear.

Snowpack Summary

10-20 cm of recent storm snow sits over the November 8 crust and a variety of old wind slabs in the alpine. The Nov 8 crust is present up to 2400 m. Faceting observed around the Oct crusts near the ground. Treeline snow depths range from 50-80 cm, and up to 110 cm in lee areas.

Avalanche Summary

On Monday a few small natural and skier triggered wind slabs in steep alpine terrain were observed on the 93 North. Sunday a natural cycle up to size 2.5 was observed in steep alpine terrain as the winds and new snow arrived. Sunday also saw a few skier triggered avalanches to size 1.5 in the new snow, occasionally stepping down to the Oct crust.

Confidence

Intensity of incoming weather systems is uncertain on Tuesday

Problems

Wind Slabs

An icon showing Wind Slabs

Moderate to strong gusty winds are expected Monday night which may lead to new wind slabs forming in the alpine for Tuesday.

  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
  • Use caution in lee areas. Wind loading could create slabs.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2.5

Persistent Slabs

An icon showing Persistent Slabs

Facets are forming around October crusts in the lower snowpack. A few avalanches have been observed stepping down into these facets or sliding on top of the October crusts. Watch for weaknesses at the base of the snowpack in steep terrain.

  • If triggered the wind slabs may step down to deeper facet layers resulting in larger avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Valid until: Nov 12th, 2019 4:00PM