Avalanche Forecast

Issued: Apr 2nd, 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 ldreier, Avalanche Canada

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Moderate to strong southwest wind will build reactive wind slabs in the alpine and at treeline. These slabs will be especially reactive where they overlie a crust.

Summary

Confidence

High -

Weather Forecast

Saturday night: Mix of clouds and clear periods, up to 3 cm snow, moderate to strong southwest wind, alpine low -6 °C, freezing level at 1100 m.

Sunday: Cloudy, up to 4 cm snow, moderate to strong southwest wind, alpine high -4 °C, freezing level at 1500 m.

Monday: Mainly cloudy, 15-20 cm snow, strong southwest wind, alpine high -4 °C, freezing level at 1500 m. 

Tuesday: Mainly cloudy, 5-10 cm snow, moderate to strong westerly wind, alpine high -6 °C, freezing level 1400 m.

Avalanche Summary

On Friday, two large (size 2) natural wind slabs were observed as well as a failed cornice that triggered a slab on the slope below and resulted in a size 2.5 avalanche. Explosives triggered small wind slabs in the alpine and a size 2.5 storm slab.

On Thursday, several wind slabs and dry loose avalanches were reported up to size 2. They likely released on Wednesday. 

On Wednesday, no significant avalanche activity was reported. Sloughing from steep terrain was seen and older wind slabs up to size 2. 

Snowpack Summary

Above 2000 m, 15-25 cm of new snow overlies up to 30 cm of denser snow that tapers rapidly with elevation. About 50-60 cm snow sit over the mid-March interface at upper elevations.

A melt-freeze crust exists on the surface up to 2000 m and higher on solar aspects. Below the crust, the top 10-30 cm of the snowpack are moist.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Wind slabs may be poorly bonded to the underlying crust.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.
  • When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.

Problems

Wind Slabs

An icon showing Wind Slabs

Moderate to strong southwest wind will build fresh and reactive wind slabs. Wind slabs can be expected in leeward terrain features in the alpine and treeline. These wind slabs will be most reactive where they overlie a slick crust.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Apr 3rd, 2022 4:00PM