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PROFESSIONAL OBSERVATION FORM
 Start Date: 01.01.19 Name: Davis, Westerdoll Operation: SAC
 Drainage/Route:  Near Lower Soldier Weather Station Observed Terrain:  5,800-8,700, N-E-S Zone/Region:  Soldier Mountains
WEATHER OBSERVATIONS
 HN24: 0 HST: Sky: VAR Precip: Temps: 18F
 Ridgeline Wind: Moderate and Gusty from the N
 Blowing Snow: L Snow Available for Transport: Small amounts
 Comments: Moderate, gusty wind from the north and east. Periods of sun and thin clouds throughout the day. What snow could be moved has done so already without a wind shift to something other than W-N-NE.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 2 Bowl between Peak 1 and Peak 2 Within past week 1.5 N NE 9,000 Pockets of wind slab that, by the look of the flanks, pulled out more than just new snow.
 3 Lunch Box (East of Smoky Dome) Within past week 2 E 9,600 Could not make out crowns but there were good sized piles in the base of the cirque.
 Comments: Avalanche activity seemed to occur early in the storm. If I had a more direct view of the Soldier Mountain Crest i'd assume there were several more D2 piles to be seen.
SNOWPACK OBSERVATIONS
 HS: South and southeast-facing terrain is where we encountered the most concerning snowpack structure. Essentially fist facets broken up by two sun or temperature crusts: HS 60 cm on 8,500' SE. See attached for pictures of pit profiles from generally deeper and stronger north and east aspects.  
 Upper Pack:  
 Middle Pack:  
 Lower Pack:  
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
45 cm

Likelihood of Triggering
Sensitivity:


Spatial Distribution:
Widespread
Terrain
  Primary Concern Comments: (12/11) Based on weather station data.
 
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
80 cm

Likelihood of Triggering
Sensitivity:


Spatial Distribution:
Widespread
Terrain
  Problem 2 Comments: I'd suspect it exists at all aspects at upper elevations. Pre-December snow. Lower Soldiers first measurable snow fell on (11/22).
 
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:


Likelihood of Triggering
Sensitivity:


Spatial Distribution:
Specific
Terrain
  Problem 3 Comments: Upper elevation distribution based on avalanche activity.
 Comments: (12/11) layer was most problematic on shallower south and southeast-facing slopes with some wind affect.
STABILITY TESTS
 Stability Test Results: (12/11) ECTNs on east and north. Several collapses and cracks shooting up to 40' on south and southeast.
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated)    
 Collapsing (isolated)    
SNOW STABILITY
 Snow Stability Rating for your observed area: Good Confidence: MODERATE Trend: Steady
 Comments (aspects and elevations of instability, etc): Fair stability on souths. MODERATE at upper and middle elevations seems reasonable given many small wind slabs in specific areas and the possibility of a persistent slab avalanche particularly on wind-affected thinner souths.
BOTTOM LINE
 Comments: The (12/11) layer was easy to find in all pit locations but was only sensitive in the thin south-facing terrain we observed at middle elevations. The one crown + bed surface we got eyes on looked to gouge into older snow. Both upper and middle elevations have taken a hit from the wind with lots of bare ridge lines as proof. The Fairfield foothills to just shy of Peak 1 and Elk Ridge do not have enough snow to cause any avalanche concerns.
FILE ATTACHMENTS

190101_Soldier_8200_N_pit.jpg
Pit on 8,200' North Aspect

190101_Soldier_8300_E_Pit.jpg
Pit on 8,300' East Aspect

190101_SoldierCatSkiTerrain_03.jpg
Small wind slab that appears to have gouged into older weak snow layers.

190101_SoldierCatSkiTerrain_00.jpg
Some D2 piles under the Lunch Box east of Smoky Dome.