Chicken Wing

SNOWPACK OBSERVATION
Submission Info
Forecaster
Thursday, March 15, 2018 - 1:30pm
Red Flags: 
Recent loading by new snow, wind, or rain
37° 45' 18.36" N, 119° 2' 13.2" W
Snowpit Observations
More detailed information about the snowpack: 

Toured up N and NW aspects of the Chicken Wing to the top twice, skiing down N, then NE-E facing trees. Looked specifically for storm slabs and persistent weak layers below treeline and sensitive wind slabs at the top. Found all three, though only the wind slabs were of any concern given our mellow terrain choice.

There is definately a grauppel layer in the recent storm snow. Below ~8800' the general structure of the upper snowpack consisted of 5-10cm of F hard new precip snow, dry; 5cm F hard grauppel, dry; 3cm 1F hard melt-freeze crust, dry; 4F moist snow down to the ground. Several hand shears failed planar and energetically in the grauppel or just under the melf-freeze crust above the moist snow, minor cracking around skis where the melt-freeze crust was breakable. Snowpack was dry top to bottom above ~8900'. No cracking and totally unconsolidated storm snow above the crust above 9000'. Hand shear above 9000' failed with much harder force.

Two sets of snowpack tests, 1st in a large opening in the trees on a NNW aspect at 8950' where snow depth was 97cm. Structure: 97 to 85cm dry F hard DFs, 85 to 81cm dry F hard grauppel, 81 to 87cm P hard MFcr, 78 to 30cm 4F to 1F rounds (0301 storm), very thing MFcr at 30cm, 30 to 8cm dry F hard rounding depth hoar, 8cm to ground 1F melt-freeze from early season. Temperature gradient was mostly under threshold for faceting except in the top 30cm. Results Test 1: CTM SC x2 at 89cm down in the depth hoar on top of the ground melt-freeze layer; CTE PC x2 in the grauppel layer; ECTP22 down 89cm in the depth hoar; ECTP24 down 67 at the top of the depth hoar under the thin MFcr. Ski pen = 15, Boot = 25.

2nd set of tests in a large opening in the trees on a NE aspect at 9500' where snow depth was 167cm. Structure similar to lower tests except there were two facet layers separated by a decomposing melt-freeze crust down 92cm and 107cm respectively. Tests results site 2: CTM PC on the graupel layer down 17cm; DTM SC down 92cm in the upper facet layer; PST 48/105 END down 107 in the lower facets; PST 28/105 END down 92cm in the upper facets. Ski pen = 20, Boot = 35.

Kick tests on very small wind loaded test slopes at the top of the ridge (9700') had small results: 20cm deep 4F hard wind packed rounds broke about 6'x8' on top of F hard grauppel and slid about 10'. Bed surface was 4F hard rounds and DFs. Slope angel was 42 degrees, NE aspect loaded by SW winds.

Sky started the moring as Few clouds and gradually became Broken clouds by 2pm when showers began (S-1). Winds were consistently L from the SE-S-SW with M gusts. Winds picked up and shifted to NW locally by 3pm. Lots of snow transport over the mountains, especially from Rock Creek S to Bishop on the drive back.

Weather Observations
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