Avalanche on Donner

Location Name: 
North of Mt. Judah
Region: 
Donner Summit Area
Date and time of avalanche (best estimate if unknown): 
Sun, 03/13/2016 - 08:30
Location Map: 
United States
39° 18' 45.7632" N, 120° 19' 30.5832" W
See map: Google Maps
US


Red Flags: 
Recent avalanche activity
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain
Terrain Trap
Observation made by: Guide at Alpenglow Expeditions
Avalanche Observations
Avalanche Type: 
Dry
Slab
Slope: 
45degrees
Trigger type: 
Skier
Crown Height: 
3 ft
Aspect: 
Northeast
Weak Layer: 
Storm Snow
Avalanche Width: 
20ft.
Terrain: 
Near Treeline
Elevation: 
7 300ft.
Avalanche Length: 
10ft.
More detailed information about the avalanche: 

Ski test on this small corniced feature was productive in showing the wind slab / cornice problem today. Stomping above this small feature was able to initiate a failure in the windslab below, which had a crown height of 2'-3', a width of about 20', and a small, 10' run. (see photo)

Very active wind slab and cornice growth was observed all day today. 

Numerous whumphs were heard in both the wind slabs and storm slabs. Shooting cracks were also observed today, but they were mostly found in freshly wind loaded features. 

Avalanche Photos: 
Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
100% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Gale Force
Precipitation: 
Snow
Air temperature trend: 
Static
Wind Direction: 
Southwest
Accumulation rate: 
Greater than 1 in. per hour
More detailed information about the weather: 

Once again, today was characterized by heavy weather. Gale force winds combined with heavy snowfall resulted in "full" conditions. Visibility ranged from 300'+ to less than 10'.