Avalanche: Turnagain

Location: Magnum

Date:
Observer:
Route & General Observations

Travelled NW Shoulder uptrack, dug pit at 3400′ and skied next open Southerly-facing field beyond PMS bowl (not sure of a name), skinned up PMS bowl and skied down shoulder uptrack to due to thick fog and lack of visibility. Fog started out in the morning above ~2000′ then broke throughout the late morning and settled between 1300~1700′ by sunset. Found up to 10cm new snow in lightly wind transported pockets. New snow was very low density sitting on a stout rain crust that persisted to about 3200′. Decent sized surface hoar observed at this interface at all elevations.

Avalanche Details
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Trigger SkierAvalanche Type Soft Slab
Aspect NorthwestElevationunknown
Slope Angle 40degCrown Depth 8in
Width 10ftVertical Run 20ft
Avalanche Details

Sluff was running quickly to valley bottom on the Southerly, skied aspect. One isolated 8"x10'x20' pocket did pop out on our traverse returning to our uptrack retreat. This was a steeper slope (aproximate 40-45deg) in a rocky wind pocket- low volume running beyond our visibility.

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

Sluff was running quickly to valley bottom on the Southerly, skied aspect. Much debris was observed buried with this weeks new light snow both on Magnum and Sunburst across the way. (All previously reported in observations)

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

Temps were in high teens. Visibility was often obscured by fog layer mentioned above. Wind was very calm with no signs of recent significant winds on snow surface.

Snow surface

Low density powder without visual wind effect. New snow depth did vary in scouring/loading areas from prevailing light East-ish wind

Snowpack

Dug a pit at 3400' on a South-facing aspect. We dug down 250cm in a commonly wind-loaded area. Snowpack height was found at 310cm. We should have descended a ways to save ourselves some work and actually get to the ground. Oh well this is what we found:

310-300cm F New Snow <--Newly buried surface hoar @10cm deep
300-275cm 4F Rounds <--ECTPN28 (Q3) @ 35cm deep
260-230cm 1F Rounds
230-60cm P Rounds

60-0cm N/O N/O

We expected to find a layer of advanced facets on the ground but unfortunately failed to reach the needed depth. In addition I would have liked to see the reactions of Jan 11th and New years BSH but I feel there is too much wind in our pit location to even identify these layers.