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PROFESSIONAL OBSERVATION FORM
 Start Date: 02.11.18 Name: Savage, Wieland, Schmidt Operation: SAC
 Drainage/Route:  Frenchman Ck with L1 avalanche class Observed Terrain:  7400-8500', many aspects but not much Southerly Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: 0 HST: 0 Sky: OVC Precip: Temps: 20's F
 Ridgeline Wind:
 Blowing Snow: None Snow Available for Transport: None
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 1 Frenchman Ck Older than a week 2 U NW 8700 Same path as 2014 fatality, ran ~900' vert, 12-18" crown, guessing it ran during 1/28-2/2 period when Headwaters slides occurred.
 1 Frenchman Ck Older than a week 1 U NE 7800 Small slide into creek bottom
 Comments: No avalanches observed on brief ride near the Frenchman Ck headwaters.
SNOWPACK OBSERVATIONS
 HS: 7800-8000': 80-120cm, depending on aspect 
 Upper Pack: W/NW: two 1cm crusts with thin FC interface/layer between them, then FC below lower crust, then some DF/mixed forms with a razor crust about 30cm down with some FC above and below
E: 2cm crust, then 5cm nicely developed small FC, then MF and razor crust about 30cm down with some FC above and below 
 Middle Pack: mixed forms down to ~5cm thick 12/19 FC layer at 35-45cm, then Thanksgiving crust 
 Lower Pack: mostly melt freeze with some mixed forms 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
50-65cm

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Widespread
Terrain
  Primary Concern Comments: Only observed the indicated aspects, depth was 12/19 layer
STABILITY TESTS
 Stability Test Results: W/NW aspect 8000': 2x ECTP, sudden planar, on 12/19 layer, also ECTN in same general area, PST 38/100 and 45/100 to end, CT21 SP
E aspect 8000': ECTP, sudden planar, 26 on 12/19 layer on, also 2 x ECTN same general area. Wieland: similar W/NW location at 7600', ECTP22 on 12/19, PST 45/100 END. SE 8100', ECTX.
SNOW STABILITY
 Snow Stability Rating for your observed area: Good Confidence: MODERATE Trend:
BOTTOM LINE
 Comments: It's been 10 days since we've seen any avalanche activity or a loading event, and high markers/smowmobilers climbing in steep terrain are not triggering anything...but bad structure and poor stability test results continue to make me think twice about steep, consequential terrain. It's getting harder to trigger 1-2' thick persistent slab avalanches each day, but I think it's still possible if you hit something in just the right place.
FILE ATTACHMENTS

180211_Frenchman_Sz2.jpg
Size 2 in path where 2014 Fatality Occurred