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ADVANCED OBSERVATION FORM
 Start Date: 01.02.18
 Drainage/Route:  Sunset Peak Observed Terrain:  West through South, from 6000 to 7900 ft in elevation Zone/Region:  Mores Creek
WEATHER OBSERVATIONS
 HN24: 0 HST: 65 Sky: CLR Precip: Temps: -4 to 0 Deg C
 Ridgeline Wind: Light from the NW
 Blowing Snow: None Snow Available for Transport: Small amounts
AVALANCHE OBSERVATIONS
None Reported
SNOWPACK OBSERVATIONS
 HS: 60 cm 
 Upper Pack: 2-3 cm of decomposing precipitation snow in top of variable hardness surface crust. 
 Middle Pack: Presence of persistent slab. 
 Lower Pack: Pencil hard layer composed of poly crystals. 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
31

Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Widespread
Where did you find this problem?
  Primary Concern Comments: 
 Comments: Snowpit at SE aspect 7500 feet elevation. 30 cm slab in top of 2 cm ice crust undermined by 7 cm thick facet layer.
check profile at https://snowpilot.org/node/4981
STABILITY TESTS
 Stability Test Results: ECTP18 Q1(SC), PST25/140, CPST23/90(Arr) both PST arrested at 60 cm after slab fractured.
Video of tests at https://vimeo.com/249471303
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Collapsing (isolated) Depth: 25 cm  
SNOW STABILITY
 Snow Stability Rating for your observed area: Poor Confidence: HIGH Trend: Steady
BOTTOM LINE
 Comments: Really surprise about the uniformity of structural weaknesses at Mores Creek Summit. Yesterday I checked the snowpack at Sunset Peak. This time I dig a pit at a SE aspect. South aspects are also exhibiting significant collapses. To be honest I was expecting the collapses to be gone by yesterday. But we experienced a big one skiing up on a 28 degree slope.

Contrasting snow pits for the last 7 days - The difference from NE and SE aspect is basically the thickness of the interface crust layer between the slab and weak facet layer [The last 4 snowsuits for Pilot and Sunset Peaks can be viewed and compared here https://snowpilot.org/node/4981, https://snowpilot.org/node/4779, https://snowpilot.org/node/4733, https://snowpilot.org/node/4893]. But their reactivity are comparable.