Negative and Hemlock Ridge behind June

SNOWPACK OBSERVATION
Negatives and Hemlock
Submission Info
Forecaster
Wednesday, March 18, 2020 - 1:00pm
37° 43' 37.668" N, 119° 5' 55.9896" W
Snowpit Observations
More detailed information about the snowpack: 

 

Toured up to the negatives from the June Lake Loop Rd near 4 seasons to check out the in-storm avalanche activity, new snow, wind effects and snowpack.  Impressive avalanches!  Many.  See: https://www.esavalanche.org/content/widespread-large-natural-activity-negatives for details.  Close to a foot of new snow from the 3 day storm around March 16th around 8000', and more up higher which has consolidated to about 2' in sheltered areas, and quite a bit more in wind drifted areas.  Toured up to 11,000' in negatives and found some ribbons of dense wind deposit.  ECT test failed on isolation in one test area of pencil hard slab, see attached video.  No failures when ski cutting across and stomping on this ribbon. Deep tap test testing the the failure interface on the slab of snow remaining in the large crown resulted in no failure, indicating that the snow that is hanging up their still from the main loading event is well bonded.  Other signs of instabiity are as follows:

-Noticeable whoomph ~9200' above Yost Lake on NE facing slope, 25° slope.  Felt to be about 10-15' around us.  Quick dig revealed a substantial layer of fist facets down in the old snow.  

-ECTP29 on NE facing slope ~9200' below Hemlock Ridge.  See attached video.  Failure in 4finger layer of facets under crust. 

Some wind transport over high peaks was seen in the morning, but wind subsided quickly during the day.  Exposed mid to upper elevation slopes quite wind effected, wind sheltered slopes boot top pow. Exposed slopes at mid elevation showed wind effects from yesterday afternoon/last night - see attached pic of skin track blown in.  Suprising amount of recent wind effects.   Very thin but adequate covereage on lower elevation slopes above road.    

Snowpack photos: 
Snowpit videos (tests, etc): 
Weather Observations
More detailed information about the weather: 

Chilly morning with partly cloudy skies, increased to mostly cloudy in the afternoon.  

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