Avalanche Forecast

Issued: Nov 27th, 2022 4:00PM

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

Avalanche Canada MH, Avalanche Canada

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An Arctic air mass approaches, bringing cold temps and light Northerly winds. The freshly formed wind slabs and the Nov 17 persistent slab remain sensitive to human triggering.

There are still many early-season hazards just below the snow surface. Bring extra warm layers and leave plenty of time to ski out in daylight at the end of your day.

Summary

Confidence

Moderate

Avalanche Summary

A natural, widespread avalanche cycle occurred early Sunday morning with numerous avalanches in the size 1.5-2.5 range and a few up to size 3.0

Natural avalanche activity is tapering off, but the persistent slab and new wind slabs will remain sensitive to human triggering.

Snowpack Summary

50cm of storm snow over the last few days accompanied by strong SW winds on Sunday has built fresh wind slabs. The Nov 17 persistent slab (surface hoar, facets, and crust) is down 60-80cm. The surface hoar (5-30mm) is largest at treeline and below.

The early season hazards are slowly being buried but still remain a concern. The height of snow at treeline is ~140cm.

Weather Summary

An Arctic airmass from the North will slide down into the region bringing cold temperatures, dry conditions, and a mix of sun and cloud on Monday. Alpine temps will range from -15 to -20.

Snow and warming temperatures are forecasted to return by Wednesday.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.

Problems

Wind Slabs

An icon showing Wind Slabs

Strong South West winds have redistributed the recent 50cm of storm snow into fresh wind slabs in the alpine and down into treeline.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2.5

Persistent Slabs

An icon showing Persistent Slabs

The Nov 17 surface hoar, facets and crust is now buried by 50-80cm of snow and has been reactive on convex rolls and steep slopes. Investigate smaller adjacent slopes before stepping out into bigger terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1.5 - 3

Valid until: Nov 28th, 2022 4:00PM