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PROFESSIONAL OBSERVATION FORM
 Start Date: 01.01.17 End Date: 01.01.17 Name: Davis', Liles Operation: SAC
 Drainage/Route:  Etna Observed Terrain:  W-NE, 6000-8200' Zone/Region:  Wood River Valley
WEATHER OBSERVATIONS
 HN24: 0 HST: 0 Sky: FEW Precip: Temps:
 Ridgeline Wind: Moderate and Steady from the W
 Blowing Snow: Prev Snow Available for Transport: None
 Comments: Valley fog south of Hailey and sneaking into Croy Canyon. A few clouds over the Boulders and Pioneers. Looked like more clouds out toward the Sawtooth. Clear over Etna. Biting wind chill. Winds capable of building slabs have already done so. Not much left unless it was lifted to Carey by strong wind.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 1 Fuji Within past week 1 HS N S 7400' Cross-loaded mid-slope.
 1 Quigley Within past week 1 HS N NE 7000' Ridgetop.
 Comments: Only observed small natural wind slab activity on a few cross-loaded slopes and ridgetops.
SNOWPACK OBSERVATIONS
 HS: 20-70 cm 
 Upper Pack: Surface hoar in sheltered W-N-NE facing terrain. Mix of DF and wind slab, both faceting.  
 Middle Pack: 4F-4F+ faceting DF in sheltered. Some RG in deeper norths. 1F slabs in wind-loaded. No notable mid-pack weaknesses found in this area.  
 Lower Pack: Lower 5-10 cm was moist depth hoar on all slopes. MFcr was present 15 cm above ground on slopes below ~6600'. 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
20-60

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Specific
Terrain
  Primary Concern Comments: Observed wind slab on most aspects. Complex wind patterns. Primarily alpine but some cross-loaded and exposed ridges at middle elevations.
 
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
20-70

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Widespread
Terrain
  Problem 2 Comments: Moist DH and FC @ GR.
STABILITY TESTS
 Stability Test Results: NE 8,000': ECTP 13 down 65 on DH. ECTN down 35 (x4). ECTX (x3). I tried ECT's in a couple locations with varying slab properties at the surface. Got one ECTP but i'm not confident it's representative of the larger picture.
SNOW STABILITY
 Snow Stability Rating for your observed area: Good Confidence: HIGH Trend: Improving
 Comments (aspects and elevations of instability, etc): MODERATE in the alpine. LOW below.
BOTTOM LINE
 Comments: Not much to be concerned with here. Some small pockets of lingering wind slab exist at middle elevations. In the alpine i'd continue to steer around steep wind-loaded slopes. I'd expect the magic recipe for a slide would involve both recent wind-load and weak snow at the ground.