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PROFESSIONAL OBSERVATION FORM
 Start Date: 01.08.18 Name: VandenBos Operation: SAC
 Drainage/Route:  Sawtooth Lake Observed Terrain:  6,300-9,800' Zone/Region:  Sawtooth Mountains
WEATHER OBSERVATIONS
 HN24: HST: 15cm Sky: SCT Precip: Temps:
 Ridgeline Wind: Light from the NW
 Blowing Snow: None Snow Available for Transport:
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 few Yesterday SS Saw a few fresh wind slabs that had released naturally on solar aspects. I suspect a near-surface facets plus subtle crust combo was the culprit.
 half dozen Older than a week As observed on new years in Fishook, numerous persistent slab avalanches failed in the Sawtooths.
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:


Likelihood of Triggering
Sensitivity:


Spatial Distribution:

Terrain
  Primary Concern Comments: Observed on solar half of the compass on wind loaded slopes.
 
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:


Likelihood of Triggering
Sensitivity:


Spatial Distribution:

Terrain
  Problem 2 Comments: All aspects at middle and upper elevations. Problem seems to be currently dormant but hard to trust the season's snowpack any further than you can pick it up and throw it.
STABILITY TESTS
 Stability Test Results:
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated)    
 Collapsing (isolated)    
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
FILE ATTACHMENTS

DSC_0874.JPG
Persistent slabs on N/NE aspect @ 8,600'. Thin wind slab also visible near ridgetop.

DSC_0977.JPG
Fresh wind slabs, likely failed on 1/6 interface. S/SE aspect @ 8,700'.