Avalanche Forecast

Issued: Dec 9th, 2022 4:00PM

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

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With the new snow and strong wind avoid riding steep wind loaded slopes, or having them above you.

 

Summary

Confidence

Moderate

Avalanche Summary

A size 1.5 avalanche was triggered by skiers entering a wind loaded slope. Thanks for the MIN Ben!

Please keep sharing your observations via the MIN; it helps strengthen our information gathering!

Snowpack Summary

Surface: Around 20 to 30 cm of new snow, but also at or near the surface you can find wind scoured, wind pressed, and of course wind slabsUpper-pack: on shaded terrain at all elevations large surface hoar (up to 10 mm) and generally unconsolidated snow. The upper snowpack consists of 20-50 cm of light but settling snow.Mid-pack: 50 cm down (maybe 70 to 100 cm in deep wind loaded areas) is a late November crust, with soft facets above. This is likely the critical snowpack weakness. Professionals are concerned about the possibility avalanches still releasing at this deeper interface.

Total snow depths remain low for early December with 70 to 120 cm at treeline and up to 180 cm in the alpine. Much of the below treeline elevation band is below the threshold for avalanches.

Weather Summary

Friday NightNext system approaching with moderate to strong southeast wind. 10 to 20 cm of snow overnight. Treeline temperatures around -5 to -10 C.

SaturdayAnother 10cm and possibly as much as 15 cm. Moderate to strong southerly wind. Temperatures warming slightly with around -5 above treeline.

Sunday

Storm ends overnight. Clearing through the day so a mix of sun and cloud depending where you are. Steady temperatures around -5 near treeline and higher. Light northerly wind

Monday

Clear. Dry. Light northerly wind. Slightly cooler, especially at lower elevations.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • The best and safest riding will be on slopes that have soft snow without any slab properties.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • Use caution above cliffs and terrain traps where even small avalanches may have severe consequences.

Problems

Wind Slabs

An icon showing Wind Slabs

Wind slabs could step down to the mid-November weakness in the middle of the snowpack.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

Soft facets on a crust about halfway down into the snowpack may become more sensitive to triggering with additional snow. Small avalanches could step down to this layer.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1.5 - 2.5

Valid until: Dec 10th, 2022 4:00PM