Observation – 3/20/2014 – John F. Stevens Canyon, Lewis Range, Glacier National Park

BNSF RAILWAY AVALANCHE SAFETY
VOLUNTARY FIELD OBSERVATIONS
(406) 863-0476 Email: richard.steiner@bnsf.com 

 

 

DATE
SUBMITTED:

TIME SUBMITTED:

OBSERVATION LOCATION

OBSERVATION
DATE:

SUBMITTED BY:

3/21/2014

        0800

Shed 4 SZ

3/20/2014

Steiner

GENERAL INFORMATION:

Ascended the looker’s right of the Burnout avalanche path to the east ridge of Snowslip Mountain.  Followed ridge to approximately 5,800 feet elevation and conducted a full snow profile.  Skinning conditions on ascent were good the entire way with many terrain features well buried and new snow to work with.  Trail breaking snow depths varied between 10 and 45 cm.  Descent conditions above 5600 feet were fair with 20 to 30 cm new snow with moderate density on a breakable crust.  Below 5600 conditions worsened as the new surface snow became far denser and underlying snow was moist and not supportive. Difficult skiing. No shooting cracks, snowpack collapsing, or audible failures.

WEATHER OBSERVATIONS:

Overcast skies with light snow and a light to moderate west wind.  Wind transport of new snow was occurring at ridgeline elevation onto easterly aspects. Air temperatures on the Canyon floor hovered around freezing or just above.  Air temperatures at upper elevations remained below freezing all day.  In the past week, 30 to 60+ cm of new snowfall has occurred in the Program Area at all elevations.

 

SNOWPACK OBSERVATIONS:

Conducted a full profile on a 32 degree East/ Northeast aspect at 5,800 feet elevation located in a periphery starting zone of Shed 4.  Snowpack depth was 300 cm (10 feet).

 

  • No significant temperature gradients throughout snowpack. Avg. T -20 C from snowpack surface to 60 cm from surface.  From 60 cm below the surface to the ground, steady snowpack temperature at 00C. t
  • Snowpack was dry throughout until the lower 30 cm which was moist.
  • Main layer of concern at this profile location was an interface of a thin decomposing crust and thin layer of mixed form snow grains located at 150 cm from the snowpack surface.  This interface was NOT obvious in the profile sidewall and not reactive to ECT or CT stability tests. However, this layer was sensitive to Shovel Shear Tests with repeated results of the Shovel Shear Test. (STE X 2).
  • Please note: the Shovel Shear Test is not quantitative in nature but rather qualitative and is a good indicator of where the snow could fail in shear and associated weak layer strength.

Also conducted a Test Pit at 5400 feet elevation on a 37 degree southeast aspect.  Snowpack at this location was 170 cm in depth and MOIST throughout.  Although layering could still be identified throughout, it appears liquid water has affected the entire snowpack and no layers were reactive to either ECT or CT stability tests.

 

AVALANCHE OBSERVATIONS:

No recent avalanche activity observed.

BNSF AVALANCHE SAFETY FIELD OBSERVATIONS SUBMITTED TO FLATHEAD AVALANCHE CENTER AND GLACIER NATIONAL PARK ARE BEING PROVIDEDED IN ACCORDANCE WITH THE TERMS AND CONDITIONS SPECIFIED GLACIER NATIONAL PARK SPECIAL USE PERMIT.  

THESE OBSERVATIONS REPRESENT SITE SPECIFIC INFORMATION INTENDED FOR THE BNSF AVALANCHE SAFETY PROGRAM AND IN NO WAY ARE TO BE CONSTRUED AS A PUBLIC/ RECREATION AVALANCHE FORECAST. 

For a quick reference of snow profile notation click here.
For a full reference check Snow, Weather, and Avalanche Guidelines.

03_20_14Shed 4D