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PROFESSIONAL OBSERVATION FORM
 Start Date: 01.05.19 Name: Lundy, Coba Operation: SAC
 Drainage/Route:  Butterfield Observed Terrain:  6800-9400', SE-E-N Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: HST: Sky: OVC Precip: Temps:
 Ridgeline Wind: Moderate from the S
 Blowing Snow: None Snow Available for Transport: Small amounts
 Comments: Temps were a bit cooler than forecasted. Winds atop Butterfield were as forecast, but some weather stations were a bit stronger than expected.
AVALANCHE OBSERVATIONS
None Reported
SNOWPACK OBSERVATIONS
 HS: 50-70cm 
 Upper Pack: Upper elevation solar: 2cm soft MFcr with FC below. A dusting of laid down SH on top of the crust.
Margins (E): FCsf
Shady (N): FCsf but didn't seem as developed or weak as E (subtle difference) 
 Middle Pack: FC, 4F to F. Single MFcr at 12/11 interface on solars (no sandwich) 
 Lower Pack: DH 3mm F  
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
11/22 & 12/11

Likelihood of Triggering
Sensitivity:
Unreactive

Spatial Distribution:
Isolated
Terrain
  Primary Concern Comments: Persistent problem isolated to where a slab still exists due to past wind effect. Depth is variable depending on wind deposition.
 Comments: We got a few small collapses on old wind slabs atop facets. Outside of wind affected areas, there is no slab to speak of.
STABILITY TESTS
 Stability Test Results: Out of curiosity, dug into a wind affected area at 9400', N. HS=125. 110cm of dense wind affected snow atop the 12/11 DH. I thought there was no way we'd get a test result with that much hard snow above the DH, but we got an ECTP26.
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Collapsing (isolated)    
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
BOTTOM LINE
 Comments: Very weak snowpack in this zone. Above about 8500', there is enough structure remaining to be barely supportable on skis. Below 8000', it was full depth sandbox facets. Some sporadic SH observed at surface, but wasn't sufficiently well developed or widespread to be an issue, especially with so much weak snow around.