VA Lakes-Dunderberg Peak -snow conditions

SNOWPACK OBSERVATION
East Shoulder Dunderberg Peak
Submission Info
Forecaster
Tuesday, December 29, 2020 - 6:45pm
Red Flags: 
Recent avalanche activity
Dunderberg peak 38° 4' 1.6608" N, 119° 15' 24.6816" W
Snowpit Observations
More detailed information about the snowpack: 

It was an absolutely spectacular day in the High Sierra with crystal clear cutter blue sky and relatively calm winds. Significant North winds had been forecasted for today, but even up to 11000ft in VA lks it was relatively calm. There was a light N breeze where we were today and I only saw significant flagging on the highest Peaks above 13000ft on the crest, most significantly on the Bishop skyline. Nice and chilly, 11F at 2pm 11000ft.

Toured up through trees on a primarily easterly aspect this afternoon on the east shoulder of Dunderberg Peak. There was 25-35cm of settling low density powder from the storm the past few days. The cool conditions and calm wind kept the new snow quality light and dry. Through sheltered trees, average snow depth was from 65-90cm and it was easy to punch a pole through to the base. Besides the light new snow on top, there was generally a 4F mid pack layer sitting on top of the well-developed November faceted snow at the base. Here I saw two distinct faceted layers with a melt freeze crust in between the two, marking the two November storms we experienced. Did not get any collapsing or cracking today through the trees or when we started breaking out of tree line at 11000ft. In sparser white bark pine there was older wind drift development and varying degrees of robust wind slab underneath the new snow.  Virtually no wind effect of new snow even in the alpine today where we traveled, not a common sight in the Sierra.

A few small loose D1 point releases both off the North side of South Peak and the East side of Dunderberg Peak. This was the extent of avalanche activity that we observed today.

Snow pit @ 11,002ft, 88E Aspect, 36deg slope

Did receive a “shear on isolation” upon performing an extended column test. A hard Pencil/Knife wind board underneath the new snow and resting on a softer thin 5cm 4F layer of graupel and decaying precipitation particles shot off as I isolated the back of the block with my cord. Although there is high variability out there in stratigraphy of snow, especially above tree line, we opted for staying in the trees and out of the alpine slopes. There were quite a few tracks up high in Red lake Bowl area and off South Peak. We found our fair share of rocks and logs and I imagine most other riders did today as well, as the new blanket of snow was practically un-wind effected and coated everything in a light magical blanket.

HS: 85cm

HNS: 25cm

CT10 Q3 @ new snow/old snow interface 25cm down

CT24 Q2 @ 35cm down, on bottom of Pencil/Knife 10cm wind board

ECTPV Shear during Isolation @ 35cm down—hard wind board on top of softer 4F graupel and decaying precipitation particle layer.

Snowpack photos: 
Snowpit videos (tests, etc): 
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