Natural avalanche on Silver Peak

Location Name: 
Silver Peak
Region: 
Cabin Creek, Deep Creek, or Pole Creek Area
Date and time of avalanche (best estimate if unknown): 
Fri, 12/21/2012 - 03:00
Location Map: 
United States
39° 13' 13.2672" N, 120° 14' 24.9144" W
See map: Google Maps
US


Red Flags: 
Recent loading by new snow, wind, or rain
Observation made by: Forecaster
Avalanche Observations
Avalanche Type: 
dry,slab,
Slope: 
40degrees
Trigger type: 
Natural
Crown Height: 
1 ft
Aspect: 
Northeast
Weak Layer: 
Old Snow
Avalanche Width: 
200ft.
Terrain: 
Near Treeline
Elevation: 
7 750ft.
Bed Surface: 
Old Snow
Avalanche Length: 
100ft.
More detailed information about the avalanche: 

Natural wind slab avalanche that appeared to happen either very late on Thursday or very early on Friday morning. The crown appeared fresh at 11:30am Friday, despite significant ongoing wind transport that will eventually cover crown and debris. Slope angle estimated based on previous experience with the area.

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: 
Cooling
Wind Direction: 
Southwest
Accumulation rate: 
Greater than 1 in. per hour
More detailed information about the weather: 

Snowfall started in the immediate area at 11:20am.