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PROFESSIONAL OBSERVATION FORM
 Start Date: 12.22.17 Name: Wieland Operation: SAC
 Drainage/Route:  Spring-King Observed Terrain:  7000-10000 Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: 0-Trace HST: 0-Trace Sky: OVC Precip: S-1 Temps:
 Ridgeline Wind: Light and Gusty
 Blowing Snow: Prev Snow Available for Transport: None
 Comments: Like Marshall, had more northerly winds. On and off S-1. Visibility also in and out during tour.
AVALANCHE OBSERVATIONS
None Reported
SNOWPACK OBSERVATIONS
 HS: 72cm on NW @ 9400'. Rest of snowpack obs from this location. 
 Upper Pack: PP on soft surface skin->15cm FC. Crusts a 56cm, 40cm and 38(Thanksgiving sandwich) 
 Middle Pack: Mostly 1F FC 
 Lower Pack: 4cm layer of Pencil hard DH on ground with weaker FC above.  
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
10-15cm

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Specific
Terrain
  Primary Concern Comments: Small dunes in middle elevation trees reactive to hard stomps breaking up to 6" thick. Not connected enough to produce anything more than Size 1 and wasn't in steep enough terrain for them to move anywhere. Did not observe any slabs in limited time spent in alpine near ridge.
STABILITY TESTS
 Stability Test Results: ECTN down 16cm on FC below crust. ECTN on DH near ground. PST 99/100 (End) down 16cm. PST 40/100 (SF) down 68cm.
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
 Comments (aspects and elevations of instability, etc): Steep solars in alpine were dust on very firm crust. All the alpine I viewed was wind-raked and scoured. Middle elevation NW/W trees were also wind affected but caught enough snow to form small dunes that took some stomping to break loose.
FILE ATTACHMENTS

P1000060.jpg
Small wind slabs