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PROFESSIONAL OBSERVATION FORM
 Start Date: 12.03.18 Name: VandenBos - OFF DUTY Operation: SAC
 Drainage/Route:  Marshall Observed Terrain:   Zone/Region:  Sawtooth Mountains
WEATHER OBSERVATIONS
 HN24: HST: Sky: Precip: Temps:
 Ridgeline Wind:
 Blowing Snow: Snow Available for Transport:
AVALANCHE OBSERVATIONS
None Reported
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:


Likelihood of Triggering
Sensitivity:


Spatial Distribution:

Terrain
  Primary Concern Comments: 
STABILITY TESTS
 Stability Test Results:
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (widespread)    
 Collapsing (widespread)    
 Comments: Widespread cracking and collapsing on the north half of the compass, more isolated but still present on solar aspects. Shady aspects continue to produce rolling collapses, shaking 6" diameter trees from over 100' away.
SNOW STABILITY
 Snow Stability Rating for your observed area: Poor Confidence: Trend: Steady
BOTTOM LINE
 Comments: Snowpack in the Sawtooths is remarkably similar to what I've been seeing in the Pioneers, White Clouds, and Galena Summit area and to that reported by all observers, at least on the northern half/two-thirds of the compass. Thus far the main differences seems to be that you encounter the pre-Thanksgiving snow at lower elevations in the Sawtooths (around ~7,500' or a touch higher), and the grain size of the FC -> DH at the bast of the pack are slightly smaller in the Sawtooths. Older snow on more solar aspects is a bit better behaved, but this extended cold drought we're in isn't doing anybody any favors. Snow at the surface is already faceting and is only getting worse by the day. With such a shallow snowpack gradients in the pack are strong and the "snow" near/at the ground continues to deteriorate. Its impressive that signs of instability (cracking and collapsing) aren't significantly easing with the passage of time, even as the "slab" of post Thanksgiving snow facets and becomes less cohesive.

*Its been quite calm for awhile, an uptick in wind would readily transport snow - I wouldn't be surprised to see even small amounts of loading resulting in activity, both at the current surface and on our DH/persistent problem