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PROFESSIONAL OBSERVATION FORM
 Start Date: 12.24.18 Name: Davis Operation: SAC
 Drainage/Route:  Baker Creek Observed Terrain:  7900-9700, Mainly S through E Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: 2 cm HST: 2 cm Sky: BKN Precip: S1 Temps:
 Ridgeline Wind: Light and Intermittent from the W
 Blowing Snow: L Snow Available for Transport: Small amounts
 Comments: In and out of banded clouds and light snow. Sporadic west wind sifting some snow on exposed ridges. Periods of sun but no appreciable warming of the snow surface.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 1 Peak Above Cunard Gulch 2 U NW 9,600' Crown blown in but still visible. Crown line was lower down below the ridgeline. Maybe where the 11/22 layer remained deep enough/intact without wind-scouring? 11/22 DH was present in my pit at 9700 NE above Brodie.
 Comments: Only one slide to report despite decent visibility to the south toward Bear Peak and into Castle Creek.
SNOWPACK OBSERVATIONS
 HS: South-facing terrain 7700-9700: 50-80 cm 
 Upper Pack: New snow and decomposing recent snow. 
 Middle Pack: Up to three distinct crusts with weak 4F and F facets between. 
 Lower Pack: Moist and wet small facets on the ground up to 8,100.  
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
35-40 cm

Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Widespread
Terrain
  Primary Concern Comments: Crust/Facet/Crust layer. Failing on FC between the crusts. And on the top side of the 12/11 facets.
 
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
80 cm

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Widespread
Terrain
  Problem 2 Comments: (11/22) Dist. based on previous obs. I dug on a NE at 9700' on the Brodie side.
 Comments: On steeper, south-facing slopes I found three distinct crusts. Some of these disappeared at lower angles but collapses occurred anyhow near the 12/11 interface.
STABILITY TESTS
 Stability Test Results: South, 25 deg slope @ 8,000': ECTP4 dwn 37 cm on FC between crusts, also identified this layer as the LOC after slope collapse at 8,500'
North, 20 deg slope @ 9,700': ECTP25 dwn 80 cm (x2) on DH
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Collapsing (widespread) Depth: 35-40 Length: up to 100'
 Comments: 3-4 good collapses including one that propagated at least 100' on a SE-facing slope at 9,600'. All collapses on southerly terrain that presented some variation of a crust + facet combo (mid elevation) or DH (mid-upper elevation).
SNOW STABILITY
 Snow Stability Rating for your observed area: Fair Confidence: MODERATE Trend: Steady
BOTTOM LINE
 Comments: I observed continued signs of instability on mid-pack and basal weak layers. I can see how it'd be easy to get lulled into a soft looking 38 deg slope right about now but continued collapses on middle and upper elevation south-facing terrain and a well defined stack of DH at the ground on upper elevations (under a relatively thin 60-80 cm of snow) will keep my terrain selection on the conservative side. I may have a couple photos to add later.