Negatives -Wind loading

Submission Info
Monday, January 22, 2018 - 12:30pm
Red Flags: 
Recent loading by new snow, wind, or rain
37° 43' 39.0648" N, 119° 5' 59.6688" W
Snowpit Observations
More detailed information about the snowpack: 

Toured off the top of June mountain, up hour glass, down ESE facin slope, back in-bounds to June, to check on windslabs.  

-Moderate consistent WSW winds actively transporting snow at the ridgetop and filling in evidence of tracks in top 100-150' in NE to SE facing chutes that were ridden yesterday and the day before (sat and sun) with wind deposited snow.  (Reports were that most every line was ridden on Saturday, and that one small skier triggered pocket released in Horst Chute (lookers left of main summit), otherwise no signs of instability, and calm winds for entire weekend).  Evidence still remained of tracks below, especially in more Easterly - SE facing chutes, but with some wind effect.  See attached video of wind transport today, and attached photo of isolated areas along ridge were skin tracks were now raised today, with many other areas along ridge stripped to rock.  A good fetch of snow blow off of ridge, and into chutes.  ECT tests (3 of them) on 25deg wind loaded slope entering a NE chute with recent windload failed with moderate force, and propogated with hard force (see attached video).  This current wind transport and test result led us not to ski the more NE facing chutes, and instead opt for the more SE facing terrain with mellower entrances and obvious ski tracks from the weekend.  (no results with ski cuts on entrance roll above tracks).  

-One pit dug just below top of Hour Glass Couloir (10,000', NE facing) to check on sensitivity of recent wind load/slab, which revealed 355cm total snow depth!!  Quite the wind loaded area.  15cm 1finger windslab ontop of fist plus snow.  ECTN15 failure at this interface.  Probing revealed great variability of windslab thickness within only a few feet.  

-Another pit dug at 11,200' just below sizeable cornice on ESE facing 46deg test slope, where occasional gusts were seen blowing snow.  CT18 Q1 60cm down; ECTP37 at 60cm down (no failure until I kept pounding after 30 ... so this isn't a standard result, but felt it was worth mentioning).  

0-5cm: Fist

5-48: Pencil

48-56: 1Finger

56-60: 4Finger

60-66: Fist ----- this is the layer tests failed on

66-past 75cm: Knife

-Spot weather ob: 11:15am, 9,700', -2.5deg C, light S wind w/ moderate gusts, 7/8 cloud cover.

-See attached photo of yesterday's skin track slightly blown in at 9800'.

-No time today to check on possible deeper persistent layer :-(.

Snowpack photos: 
Snowpit videos (tests, etc): 
Weather Observations
Blowing Snow: 
Air temperature: 
Wind Speed: 
Air temperature trend: 
Wind Direction: 
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More detailed information about the weather: 
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