Avalanche: Turnagain

Location: Cornbiscuit & Magnum

Route & General Observations

One last ski day before snow starts to fall on these facets. CB Southface > CB Northern Chute > Magnum SW Shoulder.

Avalanche Details
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Trigger SkierRemote Trigger Unknown
Avalanche Type Hard SlabAspect West
Elevation 2000ftSlope Angleunknown
Crown Depth 5inWidth 15ft
Vertical Run 20ft  
Avalanche Details

Very small wind slab triggered by our party on a steep roller on southern edge of Magnum West face, right at the top of alder line. Suspected weak layer of the surface facets buried by wind transported snow.

First turn of Cornbiscuit chute took away a considerable amount of snow, quickly picking up speed for a high volume and long running sluff.

Weather & Snow Characteristics
Please provide details to help us determine the weather and snowpack during the time this observation took place.

Broken to scattered skies with a much welcomed blue hole over the heart of Turnagain Pass persisting for much of the day. By the drive out (4:45pm) the ridgelines were obscured.
Mostly calm air.
Balmy temperatures compared to the last couple of couple of weeks.
Some snow crystals falling through the air at our high point on Magnum (~3000’, 3:45pm) but didn’t persist.

Snow surface

Still generally the soft faceted snow. Some areas of wind affect.
Sluffing in appropriate terrain


Correction to Magnum Ob from 1/4/19: the rain crust beneath the surface snow disappears right below 2600’. I believe what I felt before was previous wind affect. In either case, at 2750’ this slightly stiffer snow below the surface has turned to facets.

Photos & Video
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