Avalanche Forecast

Issued: Feb 25th, 2023 4:00PM

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

Avalanche Canada jpercival, Avalanche Canada

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Wind slabs are the main concern. Seek out sheltered and low-consequence terrain for the best and safest riding.

Triggering a deep persistent slab remains possible, especially in areas with a thin snowpack.

Summary

Confidence

Moderate

Avalanche Summary

New snow may form soft slabs that easily slide on the firm surfaces it is falling on.

Natural wind slab avalanches, some triggered by cornice fall, are reported up to size 3 in the northern part of the region. These avalanches highlight the importance of giving cornices a wide berth and avoiding the overhead hazard they present.

On Thursday a size 3 deep persistent slab avalanche occurred naturally near Kispiox. It was on a steep, alpine feature, failing near rocks at ridgecrest. On Wednesday at Hudson Bay Mountain, a size 2.5 deep persistent slab avalanche was triggered by cornice fall. Several size 2-3 explosive controlled deep persistent slab avalanches also occurred near Ningunsaw.

If you go into the backcountry this weekend, please consider submitting a MIN report.

Snowpack Summary

Reports of new snow amounts totaling 40cm of low density have been submitted. Expect this new snow to be easily redistributed by southwest winds and touchy to sliding on steep old stiff surfaces.

New snow will fall on a firm, wind affected surface in all exposed areas. In sheltered areas, surface faceting due to cold temperatures and/or soft surface snow may remain.

Several crusts, layers of facets, or surface hoar can be found in the top 1.5 meters of the snowpack. This mid-pack is generally showing good strength.

Weak layers of note are facets near the bottom of the snowpack, 150 to 200 cm below the surface.

The total height of snow at treeline is between 200 and 280 cm.

Weather Summary

Saturday Night

Cloudy 5 to 20 cm of low density snow, moderate southwest winds dropping light throughout the day, treeline temperatures -10°C to -15°C.

Sunday

Mostly cloudy, chance of snow flurries, winds west 30 km/h, treeline temperatures -12 ºC.

Tuesday

Cloudy, light snow flurries, winds southwest 20 km/h , treeline temperatures -10 ºC.

Monday

Cloudy, light snow flurries, winds southwest 20 km/h , treeline temperatures -10 ºC.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
  • Be mindful that deep instabilities are still present and have produced recent large avalanches.
  • Avoid areas with a thin or variable snowpack.
  • Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.

Problems

Wind Slabs

An icon showing Wind Slabs

Stiff wind slabs formed this week due to strong winds. Be sure to investigate underneath fluffy new snow for signs of wind slab. New snow may also form wind slabs in exposed areas.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

We continue to receive reports of large deep persistent slab avalanches, failing on facets (weak sugary crystals) near the base of the snowpack. Although triggering an avalanche on these deeply buried layers is unlikely, the result would be a large destructive avalanche.

Avoid shallow areas, and steep, rocky start zones.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

2 - 3.5

Loose Dry

An icon showing Loose Dry

Up to 40 cm of new low density light and dry snow overlies stiff old surfaces.

Expect that dry loose avalanches will be certain on very steep terrain. Even a small loose dry avalanche can have enough mass to push a person into or over a terrain trap such as a cliff or depression.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Certain

Expected Size

1 - 2

Valid until: Feb 26th, 2023 4:00PM