Natural Wind Slab Avalanches on South Peak, Virginia Lakes

AVALANCHE OBSERVATION
South Peak

Drainage:

Submission Info
Clancy Nelson
Forecaster
Wednesday, January 10, 2018 - 11:00am
Red Flags: 
Recent avalanche activity
Recent loading by new snow, wind, or rain
Obvious avalanche path
Avalanche Type: 
Dry
Slope: 
35degrees
Trigger type: 
Natural
Crown Height: 
2 ft
Aspect: 
Northeast
Weak Layer: 
Unknown
Avalanche Width: 
80ft.
Terrain: 
Above Treeline
Elevation: 
11 300ft.
Bed Surface: 
Unknown
Avalanche Length: 
900ft.
Number of similar avalanches: 
3
Number of partial burials: 
0
Number of full burials: 
0
More detailed information about the avalanche: 

At least 3 natrual wind slab avalanches observed on NE aspects of South Peak in the Virginia Lakes area this morning. After talking with another group who began their tour about an hour before us, the slides probably occured between 1030 and 1130am. First video is of conditions on South Peak as viewed from the trailhead parking area around 1100am. Second video was taken from the toe of the largest avalanche. All observed were D2. Release was probably at the interface of soft storm snow below overlying wind slabs. However, we did not go up to investigate the crowns because there was still consistent wind loading, plenty of snow that had not yet slid in the start zones, and we had already closed that terrain for ourselves today given the likelihood of wind slab avalanches in the alpine.

See snowpack observation from our tour for more about conditions.

Snowpit or crown profile photo or graph: 
Map of the 3 observed avalanches.
Avalanche observation video: 
Air temperature: 
Precipitation: 
Air temperature trend: 
Wind Direction: 
Accumulation rate: 
More detailed information about the weather: 
Number of People Caught: 
0
38° 2' 23.19" N, 119° 15' 18.1692" W
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