Avalanche Forecast

Issued: Mar 11th, 2022 4:00PM

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

Avalanche Canada wlewis, Avalanche Canada

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Watch for wind loading around ridgelines and mid slope terrain features. 

Use extra caution around sheltered treeline features where buried surface hoar may increase reactivity and avalanche size. 

Summary

Confidence

Moderate - Uncertainty is due to the track & intensity of the incoming weather system.

Weather Forecast

Light snowfall tapers off Saturday afternoon. Sunday brings a brief break in the snow and wind with another active front forecast to hit late evening.

FRIDAY NIGHT: Cloudy, 5 cm of snow overnight. Moderate to strong southwest wind, freezing levels drop to 500 m overnight. 

SATURDAY: Mostly cloudy. Isolated flurries possible with moderate westerly winds. Freezing levels reach 1000 m over the day, alpine high of -2. 

SUNDAY: A mix of sun and cloud with isolated flurries. Light to moderate westerly winds. Freezing levels around 1000 m. Alpine high -1.

MONDAY: Snowfall begins overnight with 5 cm by morning and another 5 cm over the day. Cloudy with moderate to strong southwest winds. Freezing levels around 1000 m. Alpine high of -1.

Avalanche Summary

On Thursday, human triggering of small wind slabs continued in specific features, commonly on east facing slopes.

This storm will provide fresh snow for strong winds to transport - expect new slabs to be more reactive to human triggers as snowfall continues.

Snowpack Summary

Storm snow accumulates over wind affected surfaces in exposed terrain and a crust on sun affected features. Soft snow can be found on north and east aspects above 1400 m. 

A layer of surface hoar buried at the beginning of March sits 10-20 cm deep. This can be found in isolated, wind sheltered areas. It was last reactive to skier traffic in the north of the region on Monday. 

The mid-February crust is now buried 40-60 cm deep. Though this layer has not produced avalanche activity, small avalanches or large loads may step down to this layer. 

The lower snowpack is well bridged by the mid-February crust, and triggering avalanches below this layer is unlikely at this time. 

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Wind slabs are most reactive during their formation.
  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

Problems

Wind Slabs

An icon showing Wind Slabs

Fresh wind slabs are forming over hard snow surfaces, and on a crust on south facing features. Buried surface hoar may exist in open treeline features that are sheltered from the wind. 

Expect most wind loading to be found on east facing slopes (lee to west/southwest winds).

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Mar 12th, 2022 4:00PM