Sunny Stahl

Location Name: 
Forecaster Observation - Whitefish Range
Observation date: 
Wednesday, February 23, 2022 - 17:15
Is this an Avalanche Observation: 
Yes
Observation made by: Forecaster

Tabs

Quick Observation

 

We went to the northern Whitefish range to look at conditions following the most recent storm.

  • We found variable wind affected surfaces above about 6500 feet.
    • The basin where we traveled seemed relatively sheltered below that elevation.
    • Above 6500 we found hard wind slabs scattered across southeast, south, and west-facing slopes. Some of these cracked easily around our skis. Some produced shooting cracks after hard stomping. These were locally up to a foot thick, and more commonly around 4-8 inches thick.
    • Above 7000 northeast winds had been dominant. The tops of northerly couliors were stripped.
  • We saw lots of small debris piles from sluffs below nearby rocky chutes, some of these had pulled out small slabs. We saw what looked to be larger slides on distant peaks, but the crowns and debris were obscured by the recent snow.
  • In our hand pits it took moderate force to pull uneven blocks in the storm snow. These broke in two layers of graupel. (More info in snowpack tab)

We avoided convex, open slopes harboring the stiff slabs in favor of treed, sheltered slopes where we skied 12 to 14 inches of soft settling powder.

 

Snowpack, Avalanche, Weather Images: 
Travel Details
Region: 
Whitefish Range - Northern (north of Coal Creek)
Activity: 
Skiing
Snowboarding
Snowmobiling
Snowpack Details
Snowpack and Weather Details: 
Hide Terrain
Elevation of observation: 
3500-5000 ft
5000-6500 ft
Above 6500 ft
Aspect(s) of observation: 
SE
S
SW
W
Red Flags: 
Shooting cracks
Persistent Weak Layers: 
Facets or Faceted Crust
Buried
Total Snow Depth: 
195
More comments about the snowpack and weather: 
We found a thin layer of graupel and small facets above the mid-February crust under the recent snow. We found that crust to summit. A second layer of graupel, mid storm snow, occasionally failed in hand pits in uneven, un-planar chunks. Wind slabs were 1F, breaking on low density, F storm snow. Sun made a cold day feel nice, but it didn't seem to affect the snow surface at mid and upper elevations. We didn't check lower elevations, but we did notice very shallow snow cover below 5000 ft.
Blowing Snow: 
None
Wind Speed: 
Light (Twigs in motion)
Wind Direction: 
Southwest
Air temperature: 
Below Freezing
Snow line: 
Valley Floor
Sky Cover: 
Mostly Clear (FEW)
Avalanche Details
Avalanche Details: 
Date and Time of Avalanche: 
Sunday, February 20, 2022 - 23:30
Number of avalanches: 
2
Avalanche Type: 
Soft Slab
Failure Plane/Weak Layer: 
Unknown
More information or comments about the avalanche: 

Timing is based on weather data and and aspect and is speculative. Triggered by sluffs off the cliffs above. Dozens of small sluffs on all aspects on surrounding peaks, probably from the same time.

Hide Trigger
Trigger: 
natural
Hide Terrain
Aspect: 
Northeast
Starting Elevation: 
above-treeline
Hide Size
Destructive Size: 
D1 Relatively harmless to people.
Relative Size: 
R1 Very Small
Avalanche Location: