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PROFESSIONAL OBSERVATION FORM
 Start Date: 12.23.18 End Date: 12.23.18
 Drainage/Route:  Mores and Summit creeks Observed Terrain:  6000-7000 feet, N through SE aspects, Zone/Region:  Mores Creek
WEATHER OBSERVATIONS
 HN24: 15 cm HST: 15 cm Sky: X Precip: S1 Temps: -3
 Ridgeline Wind: Light and Intermittent from the S
 Blowing Snow: None Snow Available for Transport: Large amounts
 Comments: Snow from last storm came in gradually.
AVALANCHE OBSERVATIONS
None Reported
 Comments: No release observed - limited visibility
SNOWPACK OBSERVATIONS
 HS: 95-105 cm 
 Upper Pack: Fist hard pow snow. Storm interface at 10 and 25 cm. Fragile crust at 35 cm depth. 
 Middle Pack: Fist to 4F rounded/sintered snow crystals with a 1 cm thick Surface Hoar and NSF layer buried 40-50 cm from the surface. Evidence of MF (not rounding) metamorphosis at the SH/NSF layer. 
 Lower Pack: Reactive basal facet layer. Structure of Basal DH layer varies at the same elevation and aspects at MCS mountains. DH is about 10 cm thick at Pilot Peak. DH is thinner and irregular at Freeman Peak. 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
90

Likelihood of Triggering
Sensitivity:
Reactive

Spatial Distribution:
Widespread
Terrain
  Primary Concern Comments: 
 
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
40-50

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Widespread
Terrain
  Problem 2 Comments: 
STABILITY TESTS
 Stability Test Results: PST30/120(END) at 90 cm, ECTP13 at 90 cm, CT13Q1(SC) at 90 cm, CT3Q2 at 25.
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Collapsing (isolated) Depth: 90 Length: 1-5 meters
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: MODERATE Trend: Improving
 Comments (aspects and elevations of instability, etc): Operationally we are sticking to the terrain with 32 degrees or less in steepness.
BOTTOM LINE
 Comments: The presence of a buried SH/NSF exhibiting "stubborn" reactivity is concerning. The possibility of triggering the SH/NSF layer that might step down into the reactive DH layer will result in an unsurvivable slide.

PST and other non-standard tests (such as CPST) at the SH/NSF interface vary with location, whereas occasionally these tests produce evidence of propagation propensity at the buried SH/NSF layer. This is the reason driving moderate confidence for snow stability and avalanche danger at MCS.
FILE ATTACHMENTS

MCSSeason2018-2019.png
Snowpack development at MCS

IMG_0032.JPG
Snowpit at Freeman Peak