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PROFESSIONAL OBSERVATION FORM
 Start Date: 02.10.19 Name: VandenBos Operation: SAC
 Drainage/Route:  Morgan Ridge Observed Terrain:  6,100-8,600' Zone/Region:  Wood River Valley
WEATHER OBSERVATIONS
 HN24: HST: Sky: VAR Precip: Temps:
 Ridgeline Wind: Light from the W
 Blowing Snow: Snow Available for Transport:
 Comments: 40cm new snow between 1900 on 2/9 and 1200 on 2/10. 50cm HST. Wind shifting from S towards NW through the course of the afternoon
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 1 Corrall Creek Today 2 SS ASr N 8,200' Remotely triggered from ridge, roughly 400' away. Failed on DH at the ground, ran over 1,000' vertical based on powder cloud, did not go to toe of debris (time considerations) or crown (safety considerations)
 1 Johnstone Peak Today 2 SS Nr 9,400' Crown and debris somewhat obscured by wind loading and additional precip. Likely occurred mid storm.
 Few East Fork Today 2 SS Nr 8,000' Several partially obscured crowns in the Mine Bender paths
SNOWPACK OBSERVATIONS
 HS: 120cm. Stats below and pit results from pit on N aspect at 6,900' 
 Upper Pack: 55cm snow from since 2/2 
 Middle Pack:  
 Lower Pack: 20-30cm DH, bone dry, showing a bit of rounding on cup edges but still a prominent ~5cm section with intact xtals and F- hardness producing results in stability tests. 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:


Likelihood of Triggering
Sensitivity:


Spatial Distribution:
Widespread
Terrain
  Primary Concern Comments: 
 
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:


Likelihood of Triggering
Sensitivity:


Spatial Distribution:
Specific
Terrain
  Problem 2 Comments: Didn't mess with wind slabs in avalanche terrain (or with avalanche terrain in general) but the ones that I observed weren't terribly touchy. Mid storm slabs were lee-ward to S/SE winds, but winds were swapping around to NW through the day and starting to pick up and deposit snow
STABILITY TESTS
 Stability Test Results: ECTN E on storm interfaces. ECTN M on 2/2. PST 19 and 21/100 END and CPST 18 and 23/100 END down 90-100cm on 12/11 DH.
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated)    
 Collapsing (isolated)    
 Comments: A few rumbling collapses on the DH where wind had added weight and some structure to the upper snowpack. One remotely triggered slide reported above.
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend: