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PROFESSIONAL OBSERVATION FORM
 Start Date: 02.11.19
 Drainage/Route:  Durrance Observed Terrain:  S --> E Zone/Region:  Wood River Valley
WEATHER OBSERVATIONS
 HN24: HST: Sky: Precip: Temps:
 Ridgeline Wind: Calm and Intermittent from the SW
 Blowing Snow: Snow Available for Transport:
AVALANCHE OBSERVATIONS
None Reported
SNOWPACK OBSERVATIONS
 HS: upper elevation 8800-9000 E aspects 160-190cm. about 50cm more in location probed on 2.9 
 Upper Pack: location dependent: on wind exposed aspects (ascent ridge) 20-30 cm windslab. 40-50 F PP in less wind affected terrain 
 Middle Pack:  
 Lower Pack:  
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
20-50

Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Specific
Terrain
  Primary Concern Comments: based on areas observed.
STABILITY TESTS
 Stability Test Results: depending on location. in areas where windslab well developed hand pits failed on isolation and propagation in ICT down 20-40cm.
ECTN on mid storm interfaces
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated) Depth: 20-40 Length: 100cm
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
BOTTOM LINE
 Comments: Much more wind effect than on 2.9 obs. SW-W-NW wind has begun to scour ascent ridge in places, filled in uptrack and non supportable windslab making ascent arduous. isolated cracking and low strength with propagation where overlying windslab well developed. skied areas where minimal wind effect, non cohesive overlying slab and low density snow made low angle skiing possible and pleasant. without wind and / or snow giving it a break think it would be hard to step down below L3 for a bit and would not be surprised if isolated windslab gets even more touchy.