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Observations

Region: Turnagain
Location: Twin Peaks (Twin Tips)
Observer:
Date:

Route & General Observations

Standard skin track up the east facing shoulder to a high point of 2700′. Looking for the distribution and reactivity of the 1/21 Buried Surface Hoar (MLK Jr BSH) layer within the snowpack. Also looking for previous buried surface hoar layers, and the changing surface conditions with the increased winds.

Red Flags

Observer Comments

Winds began to pick up around 1300 (1pm). Could see transport off most high peaks.

Weather

Weather

Low 20s F
Light to Moderate Winds - Gusting to 25mph
Few Clouds - moving in around 1pm
No Precip

Snow Characteristics

Snow surface

Road to ~1150' - A thin eggshell moisture crust decreasing to 1"of soft snow on top of a supported surface.
~1150'- Loss of the supportable surface crust.
~1300' - 2" of soft snow on top of a thin crust sandwich with 1mm facets in between two crusts.
~1500' - Loss of crust sandwich, 8" of soft snow on top of a 6" crust interface.

Snowpack

The MLK Jr Day (1/21) BSH layer was found in test pits dug between 2300' and 2700'. In both of these pits we found a mixture of BSH as well as faceting occurring near these layers. All pit locations presented propagation propensity on or involved with the MLK Jr Day BSH.

Twin Peak Test Pit 1- 2250' - HS: 140cm - E Aspect - 28*
CT19 / CT26 failed 40cm down on MLK layers (MF crust /BSH/.5mm facets/MF)
ECTP13 /ECTP23 failed 40cm down on MLK layers (MF crust /BSH/.5mm facets/MF)

Twin Peak Test Pit 2 - 2300' - HS: 130 - E Aspect - 31*
STE failed 25cm down on MF/BSH - large obvious upright BSH (5-7mm) within facets (.5mm)
CT6 failed 25cm down on MF/BSH
ECTP9 / ECTN12 failed 25cm down on MF/BSH

Twin Peak Test Pit 3 - 2700' - HS:160 - E Aspect
Tests failing directly below the BSH (3-4mm) under thin crust within facet layer (.5mm)
CT17 failed 25cm down on thin crust/facet layer
ECTP25 / ECTN17 failed 25cm down on thin crust/facet layer

Photos & Video

Photos



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