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PROFESSIONAL OBSERVATION FORM
 Start Date: 01.08.19 Name: Davis, Frost Operation: SAC
 Drainage/Route:  Soldier Creek, Soldier Cat Ski Terrain Observed Terrain:  5800-9000, All Zone/Region:  Soldier Mountains
WEATHER OBSERVATIONS
 HN24: 0 HST: 0 Sky: VAR Precip: Temps: 30F
 Ridgeline Wind: Light from the W
 Blowing Snow: Prev Snow Available for Transport: Large amounts
 Comments: High thin clouds for a good portion of the day. Steep south facing slopes warmed enough to cause some roller balls and will form a crust overnight.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 1 Soldier Creek Yesterday 1.5 HS U NE 6000' Suspected remote trigger from one gully south. Observer saw the powder cloud.
 1 N. Fork Soldier Creek Yesterday 1 HS N E 6500' Slide occurred before sled track. See photo.
 6 Fairfield Foothills Yesterday 1.5 HS N E 5300' Size limited by terrain. All breaking along and below wind lips from strong wind during the last storm.
 4 S. Fork Soldier Creek Yesterday 1 SS N S 6000' (1/5) interface with little or no wind affect.
 1 Peak 2 Yesterday 1.5 HS N NE 9000' Steep wind-loaded terrain.
 1 Peak 2 Yesterday 1 N E 9200' Multiple layers of wind slab?
 1 Peak 1 Yesterday 2 SS N N 8500' Ran on new old interface. Approximately 1,000' wide. Also slid during the 12/20 storm.
 Comments: I was able to pick out some larger crowns in the western Smokys but the images are poor and locations are unknown. For the most part it seemed that the activity was confined to storm snow. The large number of small slides at lower elevation are likely due to the very shallow and weak snowpack prior to this storm along with the intense wind loading that occurs with west and north wind in the Soldier Foothills.
SNOWPACK OBSERVATIONS
 HS: 100-125 cm on 8,800' SE 
 Upper Pack: 30 cm recent storm snow 
 Middle Pack: Some older wind slab and facet layers 
 Lower Pack: 12/11 is down 75 cm in this location 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
25-60 cm

Likelihood of Triggering
Sensitivity:


Spatial Distribution:

Terrain
  Primary Concern Comments: Based on recent avalanche activity.
 
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
25-30 cm

Likelihood of Triggering
Sensitivity:


Spatial Distribution:

Terrain
  Problem 2 Comments: (1/5) Cluster of slides occurred on these middle and lower elevation slopes. Some without wind affect.
 
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
75 cm

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Widespread
Terrain
  Problem 3 Comments: (12/11) still showing that it can propagate in large column tests but seems unlikely in most areas.
STABILITY TESTS
 Stability Test Results:
SNOW STABILITY
 Snow Stability Rating for your observed area: Fair Confidence: MODERATE Trend: Improving
BOTTOM LINE
 Comments: I'd be most concerned with pockets of wind slab over a previously thin snowpack like those responsible for the slides at low elevations and on the margins of wind swept areas at middle and upper elevations.
FILE ATTACHMENTS

190108_NFSoldierCreek_WindSlab_01.jpg
This natural slab avalanche occurred on a south-east facing slope in the N. Fork Soldier Creek drainage.

190108_Peak1_PersSlab_N_8500_06.jpg
This slab avalanche occurred on a north facing slope at 8,500' on Peak 1 near Soldier Mountain Ski Resort. It propagated approximately 1,000' wide and involved recent storm snow that fell since Jan. 5th.

190108_Peak2_WindSlab_NE_9000_04.jpg
This wind slab avalanche occurred on Peak 2 on a NE facing slope at 9,000'.

190108_Soldier_8800_SE_Pit.jpg
Snow pit.

190108_SoldierCreek_WindSlab_02.jpg
Soldier Creek wind slab. 6,000' NE