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PROFESSIONAL OBSERVATION FORM
 Start Date: 03.30.17 Name: Savage Operation: SAC
 Drainage/Route:  Galena Summit - Cross side Observed Terrain:  8600-9000', all aspects Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: 10-15cm HST: 10-15cm Sky: OVC Precip: S-1 Temps: 0 to -2C
 Ridgeline Wind: Moderate and Intermittent from the E
 Blowing Snow: M Snow Available for Transport: Small amounts
 Comments: Short tour from 1500-1630hrs. Hard to discern exact HN24 and HST due to wind effects. Sky varied from OBS to BKN. Winds were strong and gusty above 9500' in this area. On the drive up, rain line was at Baker/Prairie Ck. On the way down at 1700, rain line had risen to Owl Creek.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
SNOWPACK OBSERVATIONS
 HS: Not observed. 
 Upper Pack: 10-15cm PP in 3 distinct layers: dense on top of lower density on top of dense. HST on top of refreezing crust with interface of melt layer FC above crust. Wet/moist snow below crust everwhere except where crust was on the surface (scoured) - better freeze on scoured slopes. Wind drifts/pillows were up to 50cm thick. 
 Middle Pack: Not observed. 
 Lower Pack: Not observed.  
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
20-50cm

Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Specific
Terrain
  Primary Concern Comments: FC on crust were worrisome, but slab was rubbery/ductile. I'm not sure it had the stiffness required for fracture. Lots of uncertainty regarding middle elevation wind slab stability and I wasn't in steep terrain to test it.
 
Avalanche Characteristics
Character/Avalanche Problem:
Loose Wet

Layer/Depth:
10-15cm

Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Isolated
Terrain
  Problem 2 Comments: SW and W aspects, where somewhat sheltered, at this elevation were on the edge of being able to push small WL involving all the new snow (failing on FC+crust). Slopes ~40* would have been problematic. A little direct sun would have quickly made things interesting.
 Comments: Wind slab problem would have been much more of an issue up another 500' in elevation with more/drier snow and stronger winds.
STABILITY TESTS
 Stability Test Results: CT2 BKN, CT5 BKN at 50cm (3/29 crust+FC) and 40cm (density change in storm snow)
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated)   Length: .5m
 Collapsing (isolated) Depth: 30cm Length: 2m
 Comments: I had 1 small collapse. The wind slabs/drifts would crack easily but the cracks quickly arrested (all<1m). The slabs all had a very "rubbery", ductile feel.
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: MODERATE Trend:
 Comments (aspects and elevations of instability, etc): Not quite enough snow for big wind slab problems at this elevation, and the winds were all over the place (varying speed and direction).
BOTTOM LINE
 Comments: Expect to find wind slabs in strange places. Upper elevations would have been scary this afternoon (strong winds, larger and more widespread wind slab) when I was at the pass. PC or clear skies could produce a nice natural WL cycle in the next couple days, assuming the wind isn't blowing too hard.