Avalanche: Turnagain

Location: Seattle Ridge

Date:
Observer:
Route & General Observations

We toured to about 2800′ and skied a few laps in the sun near the uptrack.

Avalanche Details
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Trigger SkierRemote Trigger No
Avalanche Type Soft SlabAspect East
Elevation 2500ftSlope Angle 35deg
Crown Depth 8inWidth 30ft
Vertical Run 50ft  
Avalanche Details

We were able to trigger multiple small soft slabs on steep rollovers. They were failing on the 11/10 layer of buried surface hoar. The slabs were still very soft (fist hardness), but that new snow has gained just enough cohesion to start propagating fractures.

Red Flags
Red flags are simple visual clues that are a sign of potential avalanche danger. Please record any sign of red flags below.
Obvious signs of instability
Recent Avalanches?Yes
Collapsing (Whumphing)?No
Cracking (Shooting cracks)?No
Observer Comments

Multiple small skier-triggered soft slabs (from our group and from others). Nothing big enough to bury a person, but this was notably different from when we were out skiing the same terrain on Friday without any slab activity.

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

Sunny and cool, no wind all day. Valley fog went up to about 1700'

Snow surface

About a foot of soft snow at the surface on top of the firmer surface from the end of the Halloween storm.

Snowpack

The soft snow on top of the 11/10 surface hoar has gained just barely enough strength to start behaving more like a slab. Not propagating very wide (~20-30'), But it was starting to make small avalanches. There is also a fresh layer of surface hoar on top, starting at about 1500' elevation.

Photos & Video
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