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ADVANCED OBSERVATION FORM
 Start Date: 01.06.18
 Drainage/Route:  Peak 9220 - Copper Mt Crest Observed Terrain:  7000-9000 feet, West, North, East, South aspects Zone/Region:  Banner Summit
WEATHER OBSERVATIONS
 HN24: 15 cm HST: 15 cm Sky: X Precip: S-1 Temps: 0 to -2
 Ridgeline Wind: Light from the W
 Blowing Snow: None Snow Available for Transport: Small amounts
AVALANCHE OBSERVATIONS
None Reported
SNOWPACK OBSERVATIONS
 HS: 150 cm 
 Upper Pack: 15 cm pow in top of 5 cm wet snow above 8000 feet. 
 Middle Pack: 40 cm slab in top of 2 cm weak layer. Below weak layer a 10 cm crust layer. Check https://snowpilot.org/node/5141 for profile. 
 Lower Pack:  
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
40

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Widespread
Where did you find this problem?
  Primary Concern Comments: Only evidence of reactivity & propagation, collapses < 8000 feet
 
Avalanche Characteristics
Character/Avalanche Problem:
Storm Slab

Layer/Depth:
20

Likelihood of Triggering
Sensitivity:
Unreactive

Spatial Distribution:
Widespread
Where did you find this problem?
  Problem 2 Comments: No evidence of instability observed
 
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
20

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Isolated
Where did you find this problem?
  Problem 3 Comments: Spider cracking
STABILITY TESTS
 Stability Test Results: CTMQ!(SC), ECTN9
Check https://vimeo.com/249999043 for stability tests.
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated)   Length: 5 meters
 Collapsing (isolated) Depth: 30-40 cm  
 Comments: Cracking of shallow soft windslab below cornice after ski cut.
Large propagating collapse at 7200 feet + West. Additional small + isolated collapses 7000-8000 feet.
SNOW STABILITY
 Snow Stability Rating for your observed area: Good Confidence: MODERATE Trend: Improving
 Comments (aspects and elevations of instability, etc): Did not find evidence of instability at slopes above 8000 feet, with the exception of soft and shallow wind slabs,
Whumpfs (collapses) observed at slopes 7000-8000 feet.
BOTTOM LINE
 Comments: Occasional (but large) collapses suggest that there are some isolated but reactive pockets of a persistent slab problem. We skied slopes that could be characterized as uniform in snowpack depth distribution and lacking complex or rocky features in order to reduce the risk of a pocket with a reactive persistent slap.