Varying crust thickness, Lost Johnny

Location Name: 
Lost Johnny drainage
Swan Range - East Side (Hungry Horse Reservoir access)
Date and time of observation: 
Thu, 02/07/2019 - 15:35
Location Map: 

Red Flags: 
Recent loading by new snow, wind, or rain
Obvious avalanche path
Terrain Trap

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

Today we took a ride into Lost Johnny.  We found overall great riding conditions beyond the end of the road (5500 ft).

Valley bottom up to 5000 ft.

  • The crust from Groundhog's Day (2/2) is 3-4 inches thick and supportable to the weight of a snowmobile.  Near the 5000 ft mark there is 5-7 inches of new light snow on top of the crust.

5000 ft to 6200 ft.

  • The Groundhogs Day crust in the mid elevations seems to split with a thicker, more supportable crust below and thin, breakable crust above.  Sandwiched in the middle is a 1 inch layer of facets.  No results, however, in our pits.
  • We were able to get yet again propagating results with hard force on the 1/17 crust (approx 65 cm down)
  • 6-8 inches of Fist hard new snow.

6200 ft and above.

  • The Groundhog crust seems to mostly disappear with the exception being South facing aspects.  On these aspects it is still thin, but provided some instabilites with the surface snow.  
  • 8+ inches of Fist hard new snow.
  • Sluffing snow on steeper terrain was evident while skiing down.  
  • There was little evidence of wind.  

We skiied steep, gladed terrain with the only signs of instabilites being sluff running in the steeper pitches.  

Snowpit or crown profile photo or graph: 
Weather Observations
Cloud Cover: 
100% of the sky covered by clouds
Air temperature: 
Below Freezing
Air temperature trend: 
Accumulation rate: 
Less than 1 in. per hour
More detailed information about the weather: 

Cold!  It seemed to warm slightly throughout the day.  Snow was falling lightly all day, with accumulations less than 1 inch by the end or our ride.  There was generally no wind, with only the ridgetops near 7000 ft seeing light breezes.


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