Avalanche Forecast

Issued: Nov 28th, 2021 4:00PM

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

Garth Lemke,

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The Icefield Parkway will be closed intermittently on Monday for avalanche control on Parkers slabs starting at 11am. Skiing will still be accessible at Hilda creek area. Check 511 for road updates. 

Summary

Weather Forecast

Monday will be cloudy, flurries, 4cm of snow, -4 C, 1600m freezing level, and 20 gusting 60 km per hour SW winds. Tuesday will bring 20cm of snow, -5 C, and 1600m freezing level. Wednesday will bring intense snowfall, 46cm of snow, -6 to -1 C, strong to extreme winds, and 2000m freezing level. 46cm is not a typo!

Snowpack Summary

15-25cm of new warm snow and light winds in the last 24 hours is bonding well to the previous surface. It is over a firmer 80cm thick midpack which is on a crust near the ground. The crust is surrounded by large and weakening Facets. There is some rain and warm temperatures impacting the lower elevations. 

Avalanche Summary

An Icefield patrol on Sunday had very poor visibility yet a few small loose dry avalanches in very steep terrain was noted. Fridays test pit at Parkers ridge at 2100m in a sheltered low elevation location had hard compression test results on the facets below the basal crust.

Confidence

Due to the number of field observations

Problems

Loose Dry

An icon showing Loose Dry

The 15-25cm of new snow appears to be settling in yet some natural activity was noted on Sunday. Be vigilant for this problem particularly approaching or climbing steep ice climbs.

  • Be careful with wind loaded pockets while approaching and climbing ice routes.
  • Be careful of loose dry sluffing in steep, confined or exposed terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Wind Slabs

An icon showing Wind Slabs

Winds recently diminished into the light range yet the region experienced many days of extreme to strong winds. Expect windslabs to be buried by the new snow.

  • Avoid steep lee and cross-loaded slopes

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

The average 1 meter snowpack has a crust near the ground surrounded by weakening large grain Facets. This is a layer to watch as our neighbors are experiencing activity on it.

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

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1.5 - 3

Valid until: Nov 29th, 2021 4:00PM