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PROFESSIONAL OBSERVATION FORM
 Start Date: 11.28.18 Name: VandenBos - OFF DUTY Operation: SAC
 Drainage/Route:  East shoulder Williams Observed Terrain:  to 8800' on the eastern side of the compass Zone/Region:  Sawtooth Mountains
WEATHER OBSERVATIONS
 HN24: 15cm HST: Sky: Precip: Temps:
 Ridgeline Wind:
 Blowing Snow: Snow Available for Transport:
 Comments: Afternoon wx obs: low clouds hanging over the Sawtooths but the sun had been out enough to crisp up solar aspects. Calm winds where I was, but I didn't enter upper elevation terrain, though it appeared that the winds had also been quite calm up high. Low clouds were very slowly moving from south to north.
AVALANCHE OBSERVATIONS
None Reported
 Comments: Aside from a pile or two of older loose debris, none observed
SNOWPACK OBSERVATIONS
 HS: 60-70cm on ESE aspect at 8800' 
 Upper Pack: HN24: 15cm 
 Middle Pack: Post thanksgiving storm snow (minus HN24): 30-35cm: 
 Lower Pack: Pre Thanksgiving snow: 15-20cm. 2-4mm, slightly moist, moderately well cemented rounds where I was digging. 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
down 50cm

Likelihood of Triggering
Sensitivity:


Spatial Distribution:

Terrain
  Primary Concern Comments: 11/22 interface. Rose represents suspected distribution, not observed distribution
 Comments: Did not enter heavily wind affected terrain but wind slabs would have been on my radar if I had
STABILITY TESTS
 Stability Test Results: ECTN 25 and 26 down 50cm (11/22)
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated)    
 Collapsing (isolated)    
 Comments: Isolated cracking and collapsing on shady aspects
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
BOTTOM LINE
 Comments: Was on the margins of where the sun had been able to work on the old snow before Thanksgiving and where it hadn't. My pit was dug on a steep enough slope with enough of a solar aspect that the old snow at the ground had been able to round and gain strength. However, with a subtle change of either aspect or slope angle the older snow was much weaker, Did not do any formal tests on shadier aspects but given how that snow felt to the skis and poles (trapdoor turns) I'd bet that it is pretty similar to what others have been seeing. Junk at the ground with an increasingly cohesive slab on top. Could be another interesting year.