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PROFESSIONAL OBSERVATION FORM
 Start Date: 02.25.18 Name: VandenBos Operation: SAC
 Drainage/Route:  McDonald Peak Observed Terrain:   Zone/Region:  Sawtooth Mountains
WEATHER OBSERVATIONS
 HN24: HST: Sky: Precip: Temps:
 Ridgeline Wind:
 Blowing Snow: Snow Available for Transport:
 Comments: Clear morning in Ketchum, Clouds hanging over the Smokys, Boulders, and Sawtooths quickly thickening mid morning. Snowing S-1 in the sawtooths by noon, with a touch of sun in the early afternoon before skies closed and snowfall winds picked up. Snowing up to S1, but generally light. 2 cm accumulation by days end.
AVALANCHE OBSERVATIONS
None Reported
 Comments: Observed several fresh windslabs along the Smoky crest while looking up Prairie Creek in the morning. Looked like touchy wind slabs on FCsf on solar aspects. Also visible in the same location were slightly older and deeper crowns of unknown vintage, probably not more than a few days old at most. No activity observed in the Boulders or Sawtooths, but visibility was poor in the Sawooths.
SNOWPACK OBSERVATIONS
 HS:  
 Upper Pack: 30-40cm new snow above stout MFcr that tapered with elevation. Small facets observed both above and below crust. 
 Middle Pack:  
 Lower Pack:  
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:


Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:

Terrain
  Primary Concern Comments: Freshly forming wind slabs were touchy in the afternoon
 
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:


Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:

Terrain
  Problem 2 Comments: 2/14 interface was stubborn to unreactive, but the general structure is poor and may just be waiting for a bit healthier of a slab to fire up.
STABILITY TESTS
 Stability Test Results:
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated) Depth: 10-20cm Length: up to 20'
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
FILE ATTACHMENTS

180225_SmokyCrestSS_BV.JPG
Fresh windslabs along the Smoky crest while looking up Prairie Creek in the morning. Looked like touchy wind slabs on FCsf on solar aspects. Also visible in the same location were slightly older and deeper crowns of unknown vintage, probably not more than a few days old at most.