Forecaster Observation - Backcountry outside of WMR, southern Whitefish Range

Location Name: 
Forecaster Observation - Backcountry outside of WMR, southern Whitefish Range
Region: 
Whitefish Range - Southern (south of Coal Creek)
Date and time of observation: 
Sat, 12/10/2016 - 12:00
Location Map: 


Red Flags: 
Recent avalanche activity
Recent loading by new snow, wind, or rain

Observation made by: Forecaster
Snowpit Observations
More detailed information about the snowpack: 

The objectives for today's tour were to: assess how the relatively warm dense snow that fell overnight reacted with the underlying thick layer of cold low density snow;  determine if the increasing wind speeds were forming wind slabs and if we could replicate stability test propagation on a sunny aspect. 

  • The new snow/old snow interface proved to be reactive. We observed 4 natural storm slab avalanches that failed at this interface. All of these were thin due to the southern Whitefish Range receiving just 3-4" overnight. The largest of these was 40 feet wide and ran 200 vertical feet.  We also observed cracking in the surface snow in various locations.
  • We observed 1 small skier triggered wind slab avalanche just outside the WMR ski area boundary at the top of Flower Point. Depth of the slab was approximately 8". The remainder of our tour was in sheltered terrain. 
  • We dug an east facing snow pit at 6400' in a sheltered location that had a depth of 125 cm. The new snow/old snow interface was 15 cm below the surface and we had easy failure in this layer (ECTN 1). There was a 1 cm rain crust 55 cm below the surface which capped a 1 cm layer of decomposing facets. We had propagation in this layer of facets (ECTP 23) with hard force.
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: 
Static
Wind Direction: 
Southwest
Accumulation rate: 
Less than 1 in. per hour
Activity: 
Skiing
Precip Rate: 
S -1; very light snowfall, trace to 0.5cm/hour