Buttermilks-Reactive fresh wind slab

Mt Locke area
Submission Info
Monday, March 23, 2020 - 5:45pm
Red Flags: 
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain
37° 15' 59.94" N, 118° 39' 0.4248" W
Snowpit Observations
More detailed information about the snowpack: 

23F @ 11515ft @ 1200pm

Returned to the same area in the basin below Mt Locke and Peak 13121 that we toured to yesterday to observe changes in stability with the new 20cm of snow we found at 11000ft and the incoming Westerly wind today. It definitely was a dramatic difference with 30-40mph West winds rapidly moving snow to leeward NE-E aspects. Our skin track from yesterday was blown in starting around 10000ft and it looked like it had snowed an additional 1cm after we departed early afternoon at elevations beneath that.

By 10500ft surface conditions were becoming stiff and slabby and upon reaching the bench where the large moraine terminates to the east of the crest, the Wind was blowing strongly from the West and loading was visually very apparent. The convex nose of the moraine was a perfect small test slope to see if the drifting snow was reactive. On this E-NE 36deg slope, I was able to trigger a soft windslab that propagated 80ft across and was from 15-45cm deep at the crown. The firmer 4F snow slid on remaining underlying F snow that was not yet wind affected and compacted.  I took a VIDEO BEFORE of the test slope before I ascended the flank to test it and a VIDEO AFTER when a windslab subsequently triggered.Josh succinctly stated this morning in the Avalanche bulletin that wind is the main architect in forming avalanches and all the wind needs is some material—(snow). There was plenty of low density snow for the wind to move today and it was actively being  redistributed, snow crystals being tumbled, broken apart and ultimately formed into wind slabs reactive to human triggers today. I found this instability primarily on convex, steep Easterly and NE slopes that were capturing wind transported snow just above tree line today. On hand pits, the top stiffened 15cm of snow would fail and pop off just with isolation on top of the residing powder below it. Shooting cracks were easily attained when travelling on any steeper slope that was actively being loaded. The alpine was quite obscured and flagging snow was apparent everywhere. Conditions cleared around 1pm while I was there and lower elevation snow below 10000ft was melting with the increased solar input.

Natural point release activity was apparent in the high parts of the basin below the crest from late week, but I did not observe any natural activity today before I left at 130pm.

Snowpack photos: 
Snowpit videos (tests, etc): 
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