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PROFESSIONAL OBSERVATION FORM
 Start Date: 01.12.19 Name: VandenBos Operation: SAC
 Drainage/Route:  Imogene Observed Terrain:  6,900-10,000' Zone/Region:  Sawtooth Mountains
WEATHER OBSERVATIONS
 HN24: HST: Sky: Precip: Temps:
 Ridgeline Wind: Calm
 Blowing Snow: Snow Available for Transport:
 Comments: Temperatures stayed pretty cool in the alpine, maybe got above 20 for a few hours but never anywhere near as warm as Titus and Vienna reported.
AVALANCHE OBSERVATIONS
None Reported
 Comments: Lots of evidence of partially masked older activity (likely during 1/5-1/7 storm). Got better eyes on the slide on Cramer that Lundy reported on 1/8. Can still see a few feet of crown, despite additional snowfall and wind transport.
SNOWPACK OBSERVATIONS
 HS: 100cm at 8,300' on sheltered SE aspect 
 Upper Pack: 40cm PP since 1/5, 4F+ at base, 4F- on top. 
 Middle Pack: 45cm of variably dense 1-2mm FCs with a few icy MFcr-FC sandwiches thrown in for good measure. 
 Lower Pack: 15 cm DH, 3-mm moist cups at the ground, pretty dry at the top with slightly smaller grains 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
40cm

Likelihood of Triggering
Sensitivity:


Spatial Distribution:

Terrain
  Primary Concern Comments: 1/5 interface. ECTN25
 
Avalanche Characteristics
Character/Avalanche Problem:
Deep Persistent Slab

Layer/Depth:
85cm

Likelihood of Triggering
Sensitivity:


Spatial Distribution:

Terrain
  Problem 2 Comments: Grading towards a deep persistent problem where the snowpack is deeper. Can't get down to it with standard ECTs but relatively short critical cut lenghts in PSTs. PST 30/100 END
STABILITY TESTS
 Stability Test Results: See above
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
FILE ATTACHMENTS

190112_Cramer.jpg