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Observation: Turnagain

Location: Tincan

Date:
Observer:
Route & General Observations

Standard up track to a high point of 3200′. Observation of conditions after the storm. Looking at how the new snow is bonding to old snow surfaces, for mid-storm layer instabilities,  if there was natural avalanche activity, overall new snow depth and distribution and wind effect.

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?No
Collapsing (Whumphing)?Yes
Cracking (Shooting cracks)?No
Observer Comments

One large whump around 2500' on a slightly southern aspect.

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

Overcast to Broken sky - visibility in and out throughout the day.
Very light snowfall (S-1)
Light ENE winds
Temps in the mid 20s

Snow surface

Up to 24" of new snow/settled powder - less in obvious wind scoured locations (2-3")
Density increasing throughout the day, by 4PM snow below 2000' had become heavy.

Snowpack

Dug multiple pits looking at the new and old interface at different elevation bands. Generally low reactivity, but at 2500' we were surprised to see consistent propagation on the 1/21 buried surface hoar layer (MLK Jr BSH) in generally shallower South East facing aspects.

Pit 1 - 1600' - W Aspect - 27* Slope - HS:200cm
Boot Pen: 65cm
New old interface 60cm down made up of small .5mm facets and some small 2-4mm BSH
CT7 down 60cm on the new old interface
ECTP21 downcm on the new old interface

Pit 2 - 2100' - SW Aspect - 26* Slope - HS:210cm
Found a 4F to 1F hardness step within the new snow 20cm down
New old interface on top of a suncrust 65cm down with .5mm facets below the MF crust
CT13 down 20cm on hardness step
CT21 down 65cm on new old interface
ECTN23 down 65cm on new old interface
Multiple smaller breaks within the new snow on different small hardness steps/mid storm layers, no propagation

Pit 3 - 2500' - SE Aspect - 24* Slope - HS:170cm
New old interface only 20cm no results. New snow appears to be bonding to the sun crust.
Shallower new snow two noticeable layers within the snowpack - one being the MLK jr BSH 55cm down made up of 4-5mm BSH and chaining faces
CT21 down 45cm on upper unnamed BSH layer
CT23 down 55cm on MLK Jr BSH layer
ECTP28 down 55cm on MLK Jr BSH layer

Pit 4- 2550' - SE Aspect - 25* Slope - HS:170cm
New old interface only 20cm down, no results. New snow appears to be bonding to the sun crust
MLK jr BSH Layer found 60cm down
ECTP on MLK Jr BSH

Pit 5- 3171 - SSW Aspect
Wind loaded zone below the ridge
CTN x 2 - no results 45cm new snow on a melt freeze crust.

Photos & Video
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