Avalanche Forecast

Issued: Feb 15th, 2023 4:00PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is considerable. Known problems include Storm Slabs and Deep Persistent Slabs.

Avalanche Canada llarson, Avalanche Canada

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As snowpack totals increase through the day, expect to find reactive storm slabs at all elevations and touchy wind slabs at treeline and alpine elevations. Conservative terrain travel is recommended.

Summary

Confidence

Moderate

Avalanche Summary

No new avalanches reported in the region.

Looking forward, storm and wind slabs will likely be reactive as the new snow settles and possibly touchy where this new snow is affected by wind like in lee (north to east) terrain features at all elevations.

The basal snowpack remains questionable and should still figure into terrain selection around steep features with shallow or variable snowpack areas where these layers may be more easily triggered by a person or machine as well as large wind slab or cornice releases.

Snowpack Summary

Snow starting overnight and continuing through the day will bring total snowfall between 20 and 30 cm to the area. This new snow coupled with moderate to strong southwest winds will be building storm slabs and wind slabs at all elevations. Cornices will also continue to grow over the next few days.

The mid-pack is gaining strength and consists of rounding facets and melt-freeze crusts that are starting to degrade.

Near the base of the snowpack, a persistent weak layer composed of large and weak facets formed in November is strengthening slowly. This layer is most likely to be triggered in thin, rocky alpine and upper treeline terrain.

Weather Summary

Wednesday night

Cloudy with snowfall, accumulation 5 to 10 cm, 30 to 40 km/h southwest winds, treeline temperatures -6 °C.

Thursday

Cloudy with snowfall, accumulation 10 to 20 cm, 20 to 30 km/h southwest winds, treeline temperatures -4 °C.

Friday

Cloudy with flurries, accumulation 2 to 5 cm, 20 to 30 km/h southwest winds, treeline temperatures -5 °C

Saturday

  • Cloudy with flurries, accumulation 2 to 5 cm, 30 to 40 km/h southwest winds, treeline temperatures -3 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Storm slab size and sensitivity to triggering will likely increase through the day.
  • Storm slabs in motion may step down to deeply buried weak layers resulting in very large avalanches.
  • In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
  • Avoid exposure to slopes that have cornices overhead.

Problems

Storm Slabs

An icon showing Storm Slabs

Roughly 15 to 30 cm of new snow over the next 36 hours will develop into storm slabs at all elevations. This storm is associated with moderate to strong southwest winds so wind slabs are possible and may be touchy as the snow starts to accumulate.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

A layer of large, weak facets sits near the base of the snowpack. This layer is most prominent in upper treeline and lower alpine elevations. Riders are most likely to trigger an avalanche on this layer in steep, shallow terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 4

Valid until: Feb 16th, 2023 4:00PM