Natural avalanche on Far East Ridge of Tamarack Peak

Location Name: 
Tamarack Peak - Far East Ridge
Region: 
Mount Rose Area
Observation Date & Time: 
Sunday, December 4, 2022 - 03:00
Location: 
39.312855, -119.911101
See map: CalTopo
Is this an Avalanche Observation?: 
Yes


Conditions Alerts:

  • Avalanche Activity
  • Other Signs of Instability (cracking, whumpfing, collapsing)
  • Other Signs of Instability (cracking, whumpfing, collapsing)›Collapsing / whumpfing noises
  • Persistent Problem
  • Recent Loading
  • Recent Loading›Blowing Snow
  • Recent Loading›More Than a Foot of New Snow

Terrain Alerts: 
Slopes Steeper than 30 degrees
Obvious Slide Path
Trigger Points
Terrain Matches the Advisory
Observation made by: Forecaster

Tabs

Observation
Description of Snow, Weather, and Avalanche Conditions: 

We saw this avalanche that appeared to have occurred naturally, triggered by cornice collapse. Storm snow covering the debris suggested it occurred sometime last night. Additional low sections of crown propagating horizontal out from the flanks lower on the slope suggest Dec 1 PWL involvement. Possibly initiated as a wind slab that triggered the PWL lower on the slope to show persistent slab behavior, making it a hybrid type avalanche.
Hide Snowpack Details
Persistent Weak Layers: 
Buried
Hide Avalanche Details
Avalanche Type: 
Persistent Slab
Failure Plane/Weak Layer: 
Old Snow
Additional number of similar avalanches: 
1
Hide Trigger
Trigger: 
Natural
Trigger Modifier: 
Cornice Fall Triggered
Hide Terrain
Start Zone Slope Angle: 
40degrees
Aspect: 
Northeast
Starting Elevation: 
near-treeline
Hide Size
Destructive Size: 
D2 Could bury, injure, or kill a person.
Crown Height: 
3 ft
Avalanche Width (Average width): 
100ft.
Avalanche Length (Vertical Run): 
200ft.
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