Forecaster Observation - Mt Penrose, Middle Fork, Flathead Range

Location Name: 
Forecaster Observation - Mt Penrose, Middle Fork,Flathead Range
Region: 
Flathead Range - Middle Fork Corridor
Date and time of avalanche (best estimate if unknown): 
Mon, 01/04/2016 - 11:00
Location Map: 

Red Flags: 
Recent avalanche activity
Obvious avalanche path
Observation made by: Forecaster
Avalanche Observations
Avalanche Type: 
Slab
Trigger type: 
Other - explain below
Aspect: 
East
Weak Layer: 
Unknown
Avalanche Width: 
80ft.
Terrain: 
Above Treeline
Elevation: 
7 600ft.
Bed Surface: 
Old Snow
Avalanche Length: 
300ft.
More detailed information about the avalanche: 

The avalanche appears to have been triggered by a small cornice fall.  The slab involved the top 12"-18" of wind deposited surface snow accumulated from winds over the past week.  Starting zone slope angle appears to be 40+ degrees.  Although the avalanche was relatively small, and debris would not bury you, the consequence of tumbling through steep rocky terrain was high.  The avalanche appeared to be recent and perhaps a day or two old.

Avalanche Photos: 
Weather Observations
Cloud Cover: 
Clear
Air temperature: 
Above Freezing
Air temperature trend: 
Warming
Activity: 
Skiing