Avalanche Forecast

Issued: Mar 7th, 2022 4:00PM

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

Avalanche Canada JSmith, Avalanche Canada

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Recently formed wind slabs may remain active to human triggers in isolated locations; especially where they are sitting on a slippery sun crust.

 Cornices are very large in many areas, be aware of what's above your head.

Summary

Confidence

High -

Weather Forecast

MONDAY NIGHT: Mostly cloudy with isolated flurries; 0-5 cm / Light north winds / Low of -19 / Freezing level surface.

TUESDAY: Mix of sun and cloud / Light northeast wind / High of -9 / Freezing level surface.

WEDNESDAY: Sunny / Light north wind / High of -10 / Freezing level surface.

THURSDAY: Mix of sun and cloud / Strong northwest wind / High of -7 / Freezing level valley bottom.

Avalanche Summary

A few natural cornice failures to size 3 were reported on Sunday; one of which, triggered a size 3 storm slab on the slope below.

Snowpack Summary

Recent west and northwest winds have formed wind slabs on lee features at treeline and above. These slabs may remain more reactive on south facing slopes where they are sitting on a slippery sun crust. Below the recent snow, there may be a layer of small surface hoar that is likely most pronounced on northerly aspects or sheltered locations.

Lower elevations have seen warm temperatures last week and have a melt freeze crust on the surface (below 1800 m near Revelstoke and below 1500 m near Blue River).

The late February weak layer combination of crust, facets and surface hoar is buried up to 40cm deep, and has been reactive mostly on south facing slopes during periods of sun. There is some uncertainty about whether this interface will remain reactive as air temperatures cool.  

Two persistent weak layers from mid February and late January are buried 50-100cm deep. These have shown limited reactivity recently, and reports suggest they are strengthening. 

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Wind slabs may be poorly bonded to the underlying crust.
  • Use ridges or ribs to avoid areas of wind loaded snow.
  • Carefully evaluate steep lines for wind slabs.
  • Minimize your exposure time below cornices.

Problems

Wind Slabs

An icon showing Wind Slabs

Recently formed wind slabs may remain active to human triggers in isolated locations; especially where they are sitting on a slippery sun crust.

Cornices are very large in many areas, be aware of what's above your head.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Mar 8th, 2022 4:00PM