Professional Observation - BNSF Avalanche Safety, John F Stevens Canyon, Glacier Park

Location Name: 
Professional Observation - BNSF Avalanche Safety, John F. Stevens Canyon, Glacier Park
Region: 
Flathead Range/Glacier National Park - John F. Stevens Canyon
Date and time of observation: 
Mon, 02/20/2017 - 12:25
Location Map: 


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

Toured up the Shed 11/10.7 ridge to the weather station at 6400 feet and just above the top of the Shed 11 avalanche path. Dug one hasty pit in the very upper reaches of the Shed 11 start zone. Descended the same route.

  • Snowpack encountered on the tour was variable. Below 5000 feet encountered a breakable crust with punchy, wet, isothermic snow underneath. Skis sometimes penetrated 50-100 cm to the ground. Very slow going and treacherous skiing. Above 5000 feet found supportable crust with about 2 cm of fresh snow on top. Travel was fast and skiing wasn’t bad.
  • No wind loading was observed on the Shed 10.7 ridge and immediate vicinity. Distant terrain was obscured and could not tell if wind-loading was occurring on terrain above 7000 feet.   
  • No shooting cracks, audible failures, or other signs of unstable snow. No rollerballs or wet loose activity observed.
  • Hasty pit at 6400’ on a 30 degree slope, S aspect. 170 cm HS (0 cm at the ground). Extended column test yielded ECTN 13 at 140 cm. This fracture occurred under a 15 cm thick layer of melt-freeze grains located immediately underneath the Feb 10 crust. The Jan 19 crust was about 80 cm below the surface, no fractures on this layer. Snowpack was moist throughout the column.
  • No recent avalanche activity observed.
Snowpack photos: 
Any other comments about the observation or links to outside pages that have more info on the observation: 

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

Weather Observations
Blowing Snow: 
No
Cloud Cover: 
100% of the sky covered by clouds
Wind Speed: 
Light (Twigs in motion)
Precipitation: 
Mixed rain and snow
Air temperature trend: 
Warming
Wind Direction: 
Southwest
Accumulation rate: 
Less than 1 in. per hour
More detailed information about the weather: 

Overcast skies, light winds from the south-southwest, and air temperatures in the high 20s-low-30s °F at elevations above 5000 feet. Intermittent periods of light to moderate snowfall above 5000 feet. Below this elevation temperatures were in the mid-30s °F and precipitation fell as a rain/snow mix. 

Activity: 
Skiing
Precip Rate: 
S1; light snowfall, 1cm/hour
High Temp. (C): 
2
Low Temp. (C): 
-1