Avalanche near the Hourglass on Tamarack Peak

Location Name: 
Tamarack Peak
Region: 
Mount Rose Area
Date and time of avalanche (best estimate if unknown): 
Tue, 12/15/2009 - 19:37
Location Map: 
United States
39° 19' 21.054" N, 119° 55' 17.796" W
See map: Google Maps
US


Red Flags: 
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain
Observation made by: Public
Avalanche Observations
Avalanche Type: 
dry,slab,
Trigger type: 
Natural
Aspect: 
Northeast
Weak Layer: 
Other
Avalanche Width: 
50ft.
Terrain: 
Below Treeline
Elevation: 
8 900ft.
Bed Surface: 
Other - explain below
Avalanche Length: 
100ft.
More detailed information about the avalanche: 

There was what looked like a decent sized natural release right about here: 39.322515,-119.92161   It started in the trees, failed at Oct. 19 layer, and ran for about 50 feet - total width was about 100'. 

Also of note was significant whoompfing at the bottom of Hourglass. We performed a couple of compression tests and a Rutschblock at the top of Tamarack and were surprised at the apparent stability. We decided to ski, albeit conservatively. At the bottom (approx. 200' below the "throat" of Hourglass, in the trees on skier's right) we reconvened to skin up and that's when it whoompfed on us. Didn't measure the area, but rough guestimate was the resulting crack ran at least 70' across the slope.

Weather Observations
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Precipitation: 
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