Pesky surface hoar in Canyon Creek

Location Name: 
Forecaster Observation - southern Whitefish Range
Observation date: 
Friday, February 4, 2022 - 14:00

Is this an Avalanche Observation: 
Yes
Observation made by: Forecaster

Tabs

Quick Observation

We traveled to the southern Whitefish Range to look for buried surface hoar and evaluate our Persistent Slab problem. We also wanted to look closely at a slide intentionally triggered by a skier Tuesday, February 1. While performing a crown profile, three local residents approached us and mentioned they had just triggered a slide. These folks provided excellent information on locating the slide and events leading up to, during and following the slide. Please visit their observation for full details: https://flatheadavalanche.org/observation/skier-triggered-avalanche-outside-wmr-boundary. FAC staff thanks this group for sharing information from their experience with the backcountry community.

  • We performed many hasty pits looking for buried surface hoar on various slopes sheltered from the wind. We only had success finding this layer on sporadic northerly slopes at mid-elevations. 
  • A soft surface slab was found intermittently and ranged from Fist to Four Finger hard.  
  • We noted an eggshell thick freezing rain crust on all aspects at the mid-elevations. 
  • The February 1 avalanche occurred on the leeward side of a saddle and failed on a layer of buried surface hoar. Due to the windy location of this site, the surface hoar was small-sized and not apparent to the naked eye. You can find more details here https://flatheadavalanche.org/observation/wmr-avalanche-and-snow-obs
  • The avalanche from February 4 failed on a layer of well-preserved surface hoar, which was easy to see and found approximately 16 - 18 inches below the surface. 
  • No other signs of instability were noted today.

 

Snowpack, Avalanche, Weather Images: 
Snowpack, Avalanche, Weather Videos: 

Pesky Surface Hoar

Travel Details
Region: 
Whitefish Range - Southern (south of Coal Creek)
Activity: 
Skiing
Snowpack Details
Snowpack and Weather Details: 
Hide Terrain
Elevation of observation: 
5000-6500 ft
Aspect(s) of observation: 
N
NE
E
SE
S
Red Flags: 
Avalanches from the past 2 days
Persistent Weak Layers: 
Surface Hoar
Buried
New Snow in the past 24 hours: 
2.00in.
Total Snow Depth: 
235 cm
More comments about the snowpack and weather: 
The winds increased in the afternoon, but transport was minimal due to the surface rain crust.
Wind Speed: 
Moderate (Small trees sway)
Wind Direction: 
Southwest
Air temperature: 
Below Freezing
Snow line: 
3000'
Sky Cover: 
Obscured by fog, etc (X)
Highest Precipitation Rate: 
Very Light Snowfall (S-1)