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ADVANCED OBSERVATION FORM
 Start Date: 02.06.19
 Drainage/Route:  Peak 1 and Peak 2 (Phillips Ck, Soldier Ck) Observed Terrain:  6600-9500', many aspects Zone/Region:  Soldier Mountains
WEATHER OBSERVATIONS
 HN24: 0 HST: 50-70cm Sky: CLR Precip: Temps: 5-15F
 Ridgeline Wind: Calm
 Blowing Snow: Prev Snow Available for Transport: Large amounts
 Comments: Strangely calm and warm in the sun but cold on the feet. Snow stayed cold on all aspects.
AVALANCHE OBSERVATIONS
None Reported
SNOWPACK OBSERVATIONS
 HS: 170-210cm on E-NE-N 7300-9000' in relatively sheltered terrain 
 Upper Pack: 50-70cm well graded PP and DF going F to 1F with a subtle graupel layer about 20-40cm below surface 
 Middle Pack: thin razor crust below 8000' at 2/2 interface (old snow surface), some minor faceting below that but mostly rounds 1F>P 
 Lower Pack: not thoroughly observed - old FC/DH crystals near the ground were getting harder/compressed where I looked at them 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
10-80cm

Likelihood of Triggering
Sensitivity:
Unreactive

Spatial Distribution:
Specific
Where did you find this problem?
  Primary Concern Comments: No cracking, and no results from several explosive tests in steep wind-loaded terrain, performed by Soldier Mt staff.
 
Avalanche Characteristics
Character/Avalanche Problem:
Deep Persistent Slab

Layer/Depth:
160-200cm

Likelihood of Triggering
Sensitivity:
Not Observed

Spatial Distribution:
Widespread
Where did you find this problem?
  Problem 2 Comments: Would have to find areas with a thin snowpack (slopes exposed to wind, rocky sloeps, etc)
STABILITY TESTS
 Stability Test Results: Some dirty shears on CT's in upper 30cm on graupel layer and mid-storm weaknesses.
ECT mod and hard, N or X, dirty shears, on 2/2 and 1/15 weak layers/interfaces.
SNOW STABILITY
 Snow Stability Rating for your observed area: Very Good Confidence: MODERATE Trend:
 Comments (aspects and elevations of instability, etc): Lower elevations had obvious wind-loading and a thinner snowpack - we did not evaluate them, and the stability rating does not apply to lower elevations.
BOTTOM LINE
 Comments: This is the deepest snowpack I've seen in the SAC advisory area. Extensive explosives testing yielded no results. We saw no obvious signs of instability. Snowpack structure looked surprisingly good in the upper 4 feet. Stability tests indicated a stable snowpack. I'd be leery of steep, mid-cirque slopes prone to graupel accumulation and near-surface persistent weak layer formation, but I was pleasantly surprised with the big picture in this area. Caveat: how far does this "micro-climate" of relatively good stability extend? I'm still leery of the surrounding mountains where the snowpack is less than 150cm deep.