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ADVANCED OBSERVATION FORM
 Start Date: 12.19.18 End Date: 12.19.18
 Drainage/Route:  Bigwood Drainige, Tweener Ridge Observed Terrain:  NE, 8700' Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: 20cm HST: 30cm Sky: BKN Precip: Temps: -6C
 Ridgeline Wind: Strong and Steady from the NW
 Blowing Snow: I Snow Available for Transport: Large amounts
 Comments: Winds were calm to moderate below ridgeline, and ridgeline wind calmed by the late afternoon.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 Numerous Galena Peak Today 2.5 HS Nu NW >9,000'
 Comments: Numerous Hard Slab Avalanches observed on NW aspects of Galena peak at Alpine elevations on slopes >35 degrees. We observed this from across the valley. These avalanches were widespread on multiple aspects in this zone
SNOWPACK OBSERVATIONS
 HS: 90cm 
 Upper Pack: 20cm of PP, F; 20cm, DF, 4f-; 1cm of SH, up to 4mm 
 Middle Pack: 20cm of RG, 4f, 10cm, RG, 1f 
 Lower Pack: 15cm, DH, 3-6mm, dry 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
SH ~45cm down from Surface

Likelihood of Triggering
Sensitivity:
Reactive

Spatial Distribution:
Widespread
Where did you find this problem?
  Primary Concern Comments: Observed this layer in Tweener ridge and Timber Bowl
 
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
DH at 0-15cm from ground

Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Widespread
Where did you find this problem?
  Problem 2 Comments: 
 
Avalanche Characteristics
Character/Avalanche Problem:
Storm Slab

Layer/Depth:
20cm below surface

Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Widespread
Where did you find this problem?
  Problem 3 Comments: 
 Comments: SH layer buried ~20181203
DH layer buried around Thanksgiving - the TURKEY layer. gobble gobble
STABILITY TESTS
 Stability Test Results: On SH layer down ~ 40cm: PST 15/100 End, ECTP15; CTM, Q2, Resistant Planar
On DH layer down ~75cm: PST 25/100 End, ECTP20
New storm layer down ~20cm: CTE Q2, RP; ECTP7
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (widespread)   Length: up to `20M
 Collapsing (widespread) Depth: ~75cm Length: up to 20M
 Comments: It is difficult to decipher between our SH and DH layers and which layer is failing on the cracks...or BOTH?!
SNOW STABILITY
 Snow Stability Rating for your observed area: Poor Confidence: HIGH Trend: Worsening
 Comments (aspects and elevations of instability, etc): Primary concern is persistent avalanche problems at the SH layer with a close second on our DH layer. We observed this problem on NW to NE aspects above 8,000' - 10,000'. SH layer observed on Tweener ridge appeared to contain grains with some rounding mixed with the primary SH grain.
BOTTOM LINE
 Comments: Poor structure throughout snowpack will be a hazard to all travelers in avalanche terrain.
Keep a tight on eye on the Surface Hoar layer and track its sensitivity. Look for locations where SH layer does not have rounded grains intermixed.
Remember, there's plenty of whip roarin' meadow braps to be had on low angles.