Professional Observation - Tunnel Creek,Flathead Range

Location Name: 
Professional Observation - Tunnel Creek,Flathead Range
Region: 
Flathead Range - Middle Fork Corridor
Date and time of observation: 
Fri, 02/10/2017 - 12:10
Location Map: 

Red Flags: 
Recent avalanche activity
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain
Rapid warming
Obvious avalanche path
Terrain Trap
Observation made by: Professional Observer
Snowpit Observations
More detailed information about the snowpack: 

We took a hike into the Tunnel Cr. drainage today.  As expected the travel was less than ideal with a crust at all elevations.  Lower in elevation the crust was breakable and manageable to ski/ride in, however at upper elevations (6000 ft +) it was supportable in ascending mode but was unsupportable for skiing down.

We did see evidence of natural avalanche activity(see photo).  We saw avalanches on all aspects, at all elevations.  It looked to us that these had ran on the Jan 19th crust and crown depths varied from 2-4 feets. 

Our pit was dug at 6500 ft on a NE aspect.  In it we found a thick(5 cm), pencil hard crust at the surface on top of 3 cm of facets.  This layer easily failed with ECTP1.  Below the crust we found a nice 1 finger slab approx 80 cm deep.  This slab was sitting on the crust from Jan 19 and while it didn't propogate in our test we did get it to fail with hard force( ECTN 23).  We presume the avalnches we could see were failing here as there was a thin layer of facets sitting on top of the crust. 

Snowpit or crown profile photo or graph: 
Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
75% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Light (Twigs in motion)
Precipitation: 
Snow
Air temperature trend: 
Cooling
Wind Direction: 
Southwest
Accumulation rate: 
Less than 1 in. per hour
More detailed information about the weather: 

As we left the area there was graupel falling. 

Activity: 
Snowboarding
Precip Rate: 
S -1; very light snowfall, trace to 0.5cm/hour