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PROFESSIONAL OBSERVATION FORM
 Start Date: 11.27.17 Name: Davis, Preuss Operation: SAC
 Drainage/Route:  Titus Ridge -> Wx Station Pk. -> Titus Cr. Observed Terrain:  7-10,000, S-E-N Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: up to 25 cm HST: up to 25 cm Sky: BKN Precip: Temps: 22 F
 Ridgeline Wind: Moderate and Intermittent from the NW
 Blowing Snow: L Snow Available for Transport: Small amounts
 Comments: Clouds parted for a bit from 1000-1300 then OVC through 1500. Some plumes of blowing snow off exposed ridge lines.
AVALANCHE OBSERVATIONS
None Reported
 Comments: No new avalanche observations.
SNOWPACK OBSERVATIONS
 HS: 60 cm on East and 90 cm on North between 9 and 10,000'. 
 Upper Pack: 15-25 cm new snow atop rain/temp crust. Storm snow well bonded but sitting on MFcr/FC/MFcr sandwich. 
 Middle Pack: Generally 1F DF's with a couple thin ice lenses at mid-depth. 
 Lower Pack: Small moist FC on East (0-20 cm) and moist striated DH on North (0-20 cm).  
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
90-100 cm

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Specific
Terrain
  Primary Concern Comments: DH and FC near/at the ground were moist in this location. ECTX (x2) but failed each time with additional loading. MFcr/FC/MFcr combo from latest warm-up showed clean shears between crusts on column tests but lacked a slab to propagate in ECT.
 
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
10-30 cm

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Isolated
Terrain
  Problem 2 Comments: Isolated to exposed ridge lines.
 Comments: I'd be interested to see how the MFcr/FC/MFcr combo uner our recent storm snow holds up to more load.
STABILITY TESTS
 Stability Test Results: 9,800' North: Easy to moderate CT scores (SP) on FC between MFcr. Mod to hard CT scores on DH (SC), ECTX (x2) but failed and propagated with additional loading steps.
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated) Depth: 10-30 cm Length: Ski width
 Comments: Isolated cracking in fresh slab along ridge lines.
SNOW STABILITY
 Snow Stability Rating for your observed area: Good Confidence: MODERATE Trend: Improving
BOTTOM LINE
 Comments: I'd keep an eye on the MFcr/FC/MFcr layer from our last warm/rain spell with formation of a slab and subsequent load. Basal facets on east (and assuming south and west) were moist, dense and small. North-facing depth hoar and facets at the ground were also moist but larger 3-4 mm and weak (fist). Skiing was supportive from top to bottom. The rain line from this morning appeared to be near 9,000' - above that HST increased quickly.
FILE ATTACHMENTS

profileN.jpg
Profile, Wx Station Peak, 9,800' N.

profileE.jpg
Profile, Wx Station Peak, 9,800' E.