June Mountain Backcountry Snowpack Observation

SNOWPACK OBSERVATION
June Mountain BC
Submission Info
Member
Saturday, February 6, 2021 - 12:30pm
Red Flags: 
June Mountain BC 37° 43' 59.9772" N, 119° 5' 20.13" W
Snowpit Observations
More detailed information about the snowpack: 

Toured and skied the June Mountain Backcountry today including avalanche terrain.  Variable surface conditions remain the most obvious observations out there.  We did not see any signs of instability.  However, looking deeper in the snowpack at this point would likely confirm weak snowpack structure.  

On that note, we were very selective in our terrain choices by avoiding the most likely slopes that might hold the danger lurking underneath.  A point of confidence for our terrain choice was a lot of significant avalanche activity that ran on the weak underlying facets.  It is my suspicion there are places where you could still trigger a large to very large avalanche on this buried weak layer.  Even if that is a rare occurence it is scary to contemplate the consequences.  That is why we focused on our terrain assessment and terrain selection.

In addition to some light wind transport shots I am including some photos of previous avalanches and debris to help illustrate the types of terrain where I think the problem exists.  Of course it is difficult to pull out a pattern or pinpoint where the next avalanche is going to occur from a few long distance photos, but these may help guide your decision making.

Snowpack photos: 
A welcome bootpack in the Hourglass.
Light wind deposits filling in the skintrack.
More wind deposits in the skintrack.
Old Persistent Slab Avalanche along the San Joaquin Ridge.  Look at the visible stauch wall!
Annotated photo of an old avalanche that ran in the negatives.
Vegetative clues from Persistent Slab Avalanche in the Negatives
Any other comments about the observation or links to outside pages that have more info on the observation: 

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Do your snow dance!

Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
Clear
Air temperature: 
Above Freezing
Wind Speed: 
Moderate
Precipitation: 
None
Air temperature trend: 
Warming
Wind Direction: 
North
Accumulation rate: 
None
More detailed information about the weather: 

It was a mild day with a slight inversion in the morning.  Winds were calm until we climbed to over 10k feet.  Then light winds until the summit of the Negatives where we found moderate winds from the North.

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