Natural and Human Triggered Avalanches on Tamarack Peak

Location Name: 
Tamarack Peak
Region: 
Mount Rose Area
Date and time of avalanche (best estimate if unknown): 
Wed, 12/26/2012 - 09:00
Location Map: 
United States
39° 19' 4.4328" N, 119° 55' 18.3144" 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
Observation made by: Professional Observer
Avalanche Observations
Avalanche Type: 
dry,slab,
More detailed information about the avalanche: 

Several natural avalanches in the Tamarack Peak area today, all windslabs failing in exposed terrain just below ridgelines.  Wind slabs were easy to trigger today on test slopes with some slopes failing while approaching the slope.  Up to 2' crown lines on these intentionally triggered avalanches.  Moderate wind transport of snow with plenty of snow still available for transport.  

The 12/2 rain crust is now buried 3-6' deep in this area.  No avalanches observed today that involved the 12/2 or 12/12 facet layers.  

 

Photo #1and #2: 2 separate natural avalanches on the East Ridge of Tamarack Peak.  9400', north aspect, 35-40 degree slopes.  Both appeared to be caused by cornice failure and happened during the storm and were partially covered up by new snow.

Photo #3:  Small natural avalanche on upper East Ridge, to the climbers left of Prolitariate Bowl.  9600', NE aspect, 35 degree slope.  Also appeared to be caused by cornice failure and was partially covered up by new snow.

Photo #4 and #5:  Windslab human triggered while approaching test slope.  9100', below treeline, north aspect, 35 degree slope.  Up to 2' crown line.

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

Light snow on and off again throughout the morning.  Cloud cover 75-100% with partial visibility at times.