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PROFESSIONAL OBSERVATION FORM
 Start Date: 01.13.17 Name: Savage Operation: SAC
 Drainage/Route:  Croy/Colorado Gulch divide area via Croy Observed Terrain:  lower and middle elevations Zone/Region:  Wood River Valley
WEATHER OBSERVATIONS
 HN24: 0 HST: 0 Sky: CLR Precip: Temps: teens F
 Ridgeline Wind: Light and Intermittent from the W
 Blowing Snow: Prev Snow Available for Transport: Small amounts
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 10-20 Croy and CO Gulch Within past week 1.5 SS N D1-2, HS and SS, all aspects, all elevations
SNOWPACK OBSERVATIONS
 HS: 40-160cm, variable, averaged 90-110cm 
 Upper Pack: rain crust from 1/11, sastrugi, soft and hard wind slabs, sastrugi that is faceting, melt freeze crust from past couple days on solars, just about anything else you can imagine 
 Middle Pack: mixed bag of DF/storm snow, wind shards, some previously damp snow from 1/9 that was wet or rained on and is now frozen 
 Lower Pack: mixed forms, some FC, some crusts 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
20-150cm

Likelihood of Triggering
Sensitivity:
Unreactive

Spatial Distribution:
Specific
Terrain
  Primary Concern Comments: wind from many different directions in the past week up here, no real pattern to wind loading other than near ridges
 Comments: I stomped and traveled on all the wind features I could find over a couple hrs...no cracking, only 1 small collapse. Many wind deposits had already cracked during the storm and a lot of the prime steep, wind-loaded terrain has slid.
STABILITY TESTS
 Stability Test Results: No tests performed, just walking on wind slabs.
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Collapsing (isolated) Depth: 40cm Length: 5m
 Comments: Lots of previous cracks, 30-150cm deep. Interesting cracks in sastrugi in many places.
SNOW STABILITY
 Snow Stability Rating for your observed area: Good Confidence: MODERATE Trend:
 Comments (aspects and elevations of instability, etc): 5400-6500'
BOTTOM LINE
 Comments: Variable surface and upper pack (rain, wind, sun, etc). Slabs and sastrugi faceting/drying out/losing strength except where very hard. Wind slabs not very reactive and appeared difficult to trigger - thinking it would take >38* slopes to cause trouble now. Hard to imagine non-wind affected terrain harboring instabilities now, but I couldn't find much sheltered terrain where I was. I would have felt comfortable skiing 35* slopes with clean runouts if I had a partner.