Avalanche Forecast

Issued: Feb 10th, 2022 4:00PM

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

Deryl Kelly,

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Daytime warming with a mixed bag of strong solar influence, rain, or loading will press the hazard to Considerable over the day. Extra caution advised in all avalanche terrain as the snowpack flexes through these first diurnal warming swings.

Summary

Weather Forecast

Cooler air filtering in behind the present weather system and will drop freezing levels to valley bottom overnight. Winds will remain strong to extreme, west-northwest at ridgetop and will gradually weaken to just strong by morning. Flurries and light snow for the bulletin region overnight. Mild, sunny and dry for Friday.

Snowpack Summary

Exposed alpine stripped to rock at ridgetop and open features. Upper snowpack subject to diurnal swings in temperature and solar effect, TL and below. Dec FC down ~20-70cm. Basal FC/DH widespread throughout forecast zone.

Avalanche Summary

Significant loose wet/wet slab avalanche cycle observed on low elevation targets through the Parkway and Maligne highway corridors. Extended emergency closures possible at any time as the snowpack adjusts to the changing conditions. Avalanche control along the Parkway produced several large avalanches impeding through traffic longer than expected.

Confidence

Intensity of incoming weather systems is uncertain

Problems

Loose Wet

An icon showing Loose Wet

Spring like warming for the bulletin region trigging a significant loose wet cycle. Sunny aspects especially active.

Aspects: East, South East, South, South West, West.

Elevations: Treeline, Below Treeline.

Likelihood

Likely

Expected Size

1 - 2.5

Wind Slabs

An icon showing Wind Slabs

Any snow available for transport has blown into lee features building hard windslab and stripping ridgetops and open features bare along the Icefields Parkway and Maligne Lake area.

  • Be aware of the potential for wide propagations due to the presence of hard windslabs.
  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

Persistent slabs sit over different weak layers depending on elevation & aspect. Above 1950m a buried facet layer down 20-40cm is the primary concern. Below 1950m, a faceting crust down 40-70 is presenting a more stubborn version of a similar problem

  • Avoid shallow snowpack areas where triggering is more likely.
  • Dig down to find and test weak layers before committing to a line.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Feb 11th, 2022 4:00PM