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PROFESSIONAL OBSERVATION FORM
 Start Date: 12.18.16 Name: Davis, Linnet Operation: SAC
 Drainage/Route:  SNRA, Murdock Creek Observed Terrain:  6,200-8,600', SE-S-W-NW Zone/Region:  Wood River Valley
WEATHER OBSERVATIONS
 HN24: 0 HST: 0 Sky: FEW Precip: Temps: n/o
 Ridgeline Wind: Moderate and Intermittent from the NW
 Blowing Snow: M Snow Available for Transport: Large amounts
 Comments: Wind moving snow off the exposed peaks of the Boulders to our north.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 Comments: A few small loose dry on E-facing ridge behind Durrance.
SNOWPACK OBSERVATIONS
 HS: 65-80 cm 
 Upper Pack: DF 
 Middle Pack: RG 
 Lower Pack: 7,200' SE: Thin layer of moist FCxr. 8,690' E and NW: 5-10 cm of 2 mm FC.  
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:


Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Specific
Terrain
  Primary Concern Comments: Observed whumpfs and/or propagating ECT's on these aspects/elevations. Would expect them on N and NE as well.
 Comments: No whumpfs on low to mid elevation SW-S-SE. Some wind affect near valley floor, but not of concern. Previous wind-loading from the SE. No recent loading or wind slabs observed.
STABILITY TESTS
 Stability Test Results: 8,690' E: ECTP22 @ GR on FC sz 2
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated)   Length: 20-100'
 Collapsing (isolated) Depth: 65 cm  
 Comments: Lots of collapsing on ascent ridge and any slope above ~7,200' facing W-NW and E.
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: HIGH Trend: Steady
 Comments (aspects and elevations of instability, etc): CONSIDERABLE applies to all upper and shaded (W-N-E) middle elevations. Basal FC and DH appear around the horn at ~8,000'. LOW at lower elevations that have a wetted or nonexistent basal FC layer. This seems to be generally on souths up to ~7,500'.
BOTTOM LINE
 Comments: This observation is from a deeper pack for this zone. I wouldn't trust >35* slopes on upper and shaded (W-N-E) middle elevations due to basal FC layer. No collapses on souths, but basal FC appeared at ~8,000'.