Avalanche Forecast

Issued: Dec 18th, 2021 4:00PM

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

Lynnea Baker,

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30 cm of unconsolidated snow is being redistributed by strong SW winds. Use caution in lees.

Summary

Weather Forecast

Sunday: Mix of Sun and cloud. Light west winds. Alpine temps high -10. Freezing levels valley bottom

Monday: Cloudy with isolated flurries. Moderate south west winds. Alpine temps high -9. Freezing levels valley bottom.

Tuesday: Cloudy with isolated flurries. Strong west winds. Alpine temps high -5. Freezing levels valley bottom.

Snowpack Summary

30 cm of unconsolidated snow is being redistributed by moderate gusting to extreme SW winds. This overlies a 20-40cm buried windslab ALP/TL atop 10cm of facet above the Dec 4 rain crust. A 20-60 cm thick Nov melt freeze crust complex completes the snowpack to ground. BTL has just reached threshold in some places. Snow depth at TL is 100 - 170.

Avalanche Summary

No new avalanches reported. Field observations limited due to visibility. If you go out into the mountains please share your observations on the Mountain Information Network.

Confidence

Forecast snowfall amounts are uncertain on Saturday

Problems

Wind Slabs

An icon showing Wind Slabs

30 cm of unconsolidated snow is being redistributed by strong winds and is creating surface windslabs. In addition a buried 20 to 40cm windslab sits on the Dec rain crust.

  • Use caution in lee areas. Recent wind loading have created wind slabs.
  • Use caution on steep lee and cross-loaded slopes

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Persistent Slabs

An icon showing Persistent Slabs

No avalanches observed on this layer this week, however with a large enough trigger this layer could produce results.

  • If triggered the wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Loose Dry

An icon showing Loose Dry

Saturdays storm snow  may remain unconsolidated in steep sheltered locations.

  • Be careful of loose dry sluffing in steep, confined or exposed terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Dec 19th, 2021 4:00PM