Avalanche Forecast

Issued: Feb 18th, 2022 4:07PM

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

Conrad Janzen,

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The amount of new snow we get will dictate how much the hazard rises on Saturday. Keep monitoring this through the day.

Avalanche control is planned for Mt Stephen and Mt Bosworth in Yoho NP on Saturday. No skiing or climbing in these areas.

Summary

Weather Forecast

A moist SW flow continues until late Saturday when a cold front arrives from the NW and temperatures start to fall. Most of the snow will be west of the divide with estimates ranging from 15-20+ cm by the end of the day and strong west winds. Treeline temperatures will stay near -5 C until the cold front arrives with freezing levels near 1700 m.

Snowpack Summary

20-45 cm of new snow has fallen in the past 48-hrs with strong west winds creating fresh wind slabs at treeline and above. Areas to the west received the most snow. These wind slabs may release easily on the various firm surfaces underneath. The Jan 30th surface hoar/sun crust interface exists 30-60 cm below the surface and is currently unreactive.

Avalanche Summary

Small wind slabs up to size 1 were reported by both SSV and LL ski resorts on Friday with ski cutting and explosive work. Small reactive wind slabs in steep terrain were reported by skiers in the Lake Louise area. Some natural sluffing up to size 1 was also observed out of steep gullies and rocky terrain in areas that got the most storm snow.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Saturday

Problems

Wind Slabs

An icon showing Wind Slabs

Fresh wind slabs will continue to develop with more snow and wind on Saturday. These will be easy to trigger, especially the ones that are sitting on a firm surface underneath. Expect to find them in most leeward and drifted slopes.

  • Watch for surface cracking and stiffer surface layers of snow.
  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Loose Dry

An icon showing Loose Dry

With more new snow and wind on Saturday we may see an increase in sluffing out of steep terrain and couloirs. Ice climbers in particular might encounter increased sluffing and spindrift in confined gullies.

  • Be cautious of sluffing in steep terrain, particularly where the debris flows into terrain traps.
  • Be careful of loose dry sluffing in steep, confined or exposed terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 1.5

Valid until: Feb 19th, 2022 4:00PM