Stillwater State Forest

Location Name: 
Stryker Ridge
Observation date: 
Thursday, March 4, 2021 - 13:00
Is this an Avalanche Observation: 
Yes
Observation made by: Public

Location

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Quick Observation

Stillwater State Forest out for a sunny day of avalanche training. Outstanding visibilty afforded us views of some big avalanche terrain.  Overall activity was surprisingly quiet given warm temps and intense solar radiation.  We found a number of crusts on top of and within the snowpack:

  • Noticed 3 x D2, and roughly 6 x D1 appear on S-SW aspects at mid and upper elevations between 1pm and 3pm.
  • Snow surface on NE aspect at 4500' consisted of surface hoar on a thin breakable crust.  This started to break down at 1pm where exposed to sun.
  • Snow surface on E aspect at 5500' consisted of a thin eggshell crust.
  • In our pits @ 5000' NE aspect we found a crust buried by roughly two feet of snow that produced hand and shovel shears with easy force.
  • No shooting cracks or whumphing.
  • Rollerball/pinwheel activity was minimal possibly due to surface crusts.
Snowpack, Avalanche, Weather Images: 
Travel Details
Region: 
Whitefish Range - Northern (north of Coal Creek)
Activity: 
Snowmobiling
Snowshoeing
Snowpack Details
Snowpack and Weather Details: 
Hide Terrain
Elevation of observation: 
3500-5000 ft
5000-6500 ft
Aspect(s) of observation: 
N
NE
E
SE
S
SW
W
NW
Red Flags: 
Avalanches from the past 2 days
Rapid or prolonged warming
Persistent Weak Layers: 
Surface Hoar
Facets or Faceted Crust
On the surface
Buried
New Snow in the past 24 hours: 
0.00in.
Total Snow Depth: 
125cm
More comments about the snowpack and weather: 
4500' NE aspect: 0.5 cm surface hoar on top of 1 cm P crust. This began to break down at 1300 hrs where exposed to sun. Pit @ 5000' NE aspect: HS = 125 cm, 1.5 cm K crust @ 65 cm, 2.5 cm K crust at 40 cm w/ wet facets facets underneath. 5500' E aspect: Very thin K crust on surface survived the heat of the day.
Blowing Snow: 
None
Wind Speed: 
Calm (No air motion)
Air temperature: 
Above Freezing
Sky Cover: 
Clear (CLR)
Highest Precipitation Rate: 
No Precipitation (NO)
Avalanche Details
Avalanche Details: 
Date and Time of Avalanche: 
Thursday, March 4, 2021 - 13:00
Number of avalanches: 
3
Avalanche Type: 
Wet Loose
Failure Plane/Weak Layer: 
Old snow
More information or comments about the avalanche: 

Noticed several D2 appear on the bigger terrain across the drain between 1300-1500 hrs

Hide Trigger
Trigger: 
natural
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Start Zone Slope Angle: 
40
Aspect: 
Southwest
Starting Elevation: 
above-treeline
Hide Size
Destructive Size: 
D2 Could bury, injure, or kill a person.
Relative Size: 
R1 Very Small
Avalanche Location: 
Date and Time of Avalanche: 
Thursday, March 4, 2021 - 13:00
Number of avalanches: 
6
Avalanche Type: 
Wet Loose
Failure Plane/Weak Layer: 
Old snow
More information or comments about the avalanche: 

A handful of D1s originating in rock outcrops.

Hide Trigger
Trigger: 
natural
Hide Terrain
Start Zone Slope Angle: 
35
Aspect: 
South
Starting Elevation: 
near-treeline
Hide Size
Destructive Size: 
D1 Relatively harmless to people.
Relative Size: 
R1 Very Small
Avalanche Location: