Avalanche Forecast

Issued: Dec 9th, 2021 4:00PM

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

Jeff Andrews,

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MIN reports speak of good to excellent riding quality in sheltered areas! Be mindful of newly formed wind slabs and our deep persistent slab problem when making terrain choices.

Summary

Weather Forecast

Friday: Scattered flurries. Accumulation: 4 cm. Alpine temperature: Low -16 C, High -14 C. Ridge wind SW: 25 to 40 km/h

Saturday: Snow. Accumulation: 25 cm. Alpine temperature: Low -13 C, High -8 C. Ridge wind SW: 20 km/h gust to 55

Sunday: Flurries: Accumulation: 6 cm. Alpine temperature: Low -21 C, High -13 C. Ridge wind SW 15 km/h gust to 45

Snowpack Summary

Incremental amounts of new snow being redistributed by moderate SW winds; exposed alpine features continue to be scoured. In sheltered areas 20-30cm settled snow sits atop a supportive midpack. Soft slab forming in open areas. Our basal crust/facet/depth hoar combo near the ground remains a layer of concern. Snowpack depth 100-140cm Icefields area.

Avalanche Summary

No new avalanches have been reported. Human triggering of large avalanches remains possible especially in features with variable thin to thick snow depths in the alpine and at treeline.

Confidence

Forecast snowfall amounts are uncertain

Problems

Wind Slabs

An icon showing Wind Slabs

Variable amount of new snow and moderate SW winds creating new windslab in lee and crossloaded features. Watch for hollow sounds and cracking. Consider testing smaller slopes before committing to larger features; windslabs could initiate deep layers.

  • Use caution in lee areas. Recent wind loading have created wind slabs.
  • Use conservative route selection, choose moderate angled and supported terrain with low consequence.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1.5 - 2.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

Triggering this layer would be a high consequence event - cautious decisions and thorough investigation is necessary. More likely to trigger this layer in transitions from thin snowpack to deeper loaded pockets or terrain features.

  • Avoid thin rocky or unsupported terrain features.
  • Use caution on open slopes and convex rolls

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3.5

Valid until: Dec 10th, 2021 4:00PM