Skier triggered slide in Red Lake Trees

Location Name: 
Red Lake Trees
Region: 
Carson Pass Area
Date and time of avalanche (best estimate if unknown): 
Sun, 11/18/2012 - 13:00
Location Map: 
United States
38° 41' 15.5544" N, 119° 58' 44.6592" W
See map: Google Maps
US


Red Flags: 
Obvious avalanche path
Observation made by: Public
Avalanche Observations
Avalanche Type: 
slab,
Slope: 
35degrees
Trigger type: 
Skier
Crown Height: 
1 ft
Aspect: 
Northwest
Weak Layer: 
Other
Avalanche Width: 
30ft.
Terrain: 
Near Treeline
Elevation: 
8 900ft.
Bed Surface: 
Old Snow
Avalanche Length: 
300ft.
More detailed information about the avalanche: 

 Test Pits dug around 8,500 on similar aspect concluded: CT 10 sp, CT 16 sp, ECT X (2x).  Weak layer is a thick icy rain crust 8-12" below the surface.  Avalanche occurred on a 35 degree slope, 310 (NW) degree aspect, elevation near 8,900', confined to an isolated gully with wind affected snow on top.  Slide triggered during second turn, and propogated 30' and slid about 150 vertical feet.  Slide released at the old snow/ new snow interface.  Smaller second slide triggered by second skier.  Avalanche rated D2, and R3, debris field was 80' long 20' wide and 5' deep. 

Avalanche Photos: 
Weather Observations
Blowing Snow: 
Yes
Air temperature: 
Below Freezing
Wind Speed: 
Strong
Precipitation: 
Snow
Air temperature trend: 
Cooling
Wind Direction: 
Southwest
Accumulation rate: 
Less than 1 in. per hour
More detailed information about the weather: