Avalanche Forecast

Issued: Feb 25th, 2023 4:00PM

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

Avalanche Canada jpercival, Avalanche Canada

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Snow continues to accumulate in small amounts and will be redistributed by moderate winds creating reactive wind slabs.

The persistent slab problem remains a concern. Choose terrain that has low consequences to manage this problem.

Summary

Confidence

Moderate

Avalanche Summary

No new avalanche observation since last weekend but this could be due to few to no reports coming from the backcountry.

Last Sunday, a size 1 wind slab was skier-triggered in a gully at treeline, reminding us that despite great riding in sheltered areas, reactive wind slabs still exist in more exposed areas. See the full report here.

The week previous, our field team observed debris from a previous large persistent slab avalanche. At least once a week evidence of large persistent slab avalanches is reported. Keep this in mind when traveling in the backcountry.

Thank you to all who contribute to the Mountain Information Network. If you head to the backcountry please help out your community by sharing your experiences.

Snowpack Summary

New snow has fallen on aging wind slabs on all aspects Approximately 30 to 50 cm down a decomposing crust, up to 5 cm thick, can be found. It appears to be bonding well to layers above and below and is widespread up to 1300 m and isolated as high as 1700 m.

A weak layer of surface hoar and facets may be buried about 90 to 140 cm deep on north-to-east aspects. This layer may rest on a harder melt-freeze crust. Where preserved, this layer, if triggered, is capable of producing very large avalanches.

Weather Summary

Saturday Night

Cloudy with possible late-day sunny breaks, 2 cm accumulation, winds north 20 to 30 km/h, treeline temperatures around -15 ºC.

Sunday

A mix of sun and cloud, trace accumulation, winds northeast 35 to 40 km/h, treeline temperatures around -20 ºC.

Monday

Mostly sunny, trace accumulation, winds north northeast 30 km/h, treeline temperatures -20 ºC.

Tuesday

Mostly sunny, trace accumulation, winds north northeast 30 km/h, treeline temperatures -25 ºC.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • The best and safest riding will be on slopes that have soft snow without any slab properties.
  • Avalanche hazard may have improved, but be mindful that deep instabilities are still present.

Problems

Wind Slabs

An icon showing Wind Slabs

New snow arrived with moderate southwest winds. Winds from earlier this week have been northeasterly. Wind slabs should be expected on all aspects at higher elevations.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Persistent Slabs

An icon showing Persistent Slabs

We continue to see the occasional avalanche on a weak layer of surface hoar and facets buried about 100 cm deep. Resulting in avalanches that propagated for hundreds of metres. Some of them were remotely triggered from hundreds of metres away. The common trend is that they are on north-to-east aspects around 1500 to 1700 m in elevation.

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

Elevations: Alpine.

Likelihood

Unlikely

Expected Size

2 - 3

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