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ADVANCED OBSERVATION FORM
 Start Date: 12.18.18
 Drainage/Route:  Galena Summit - North Side Observed Terrain:  North and West facing slopes, intermediate to heavy tree density slopes, Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: 10cm HST: 10cm Sky: OVC Precip: S3 Temps: -4 to -6 C
 Ridgeline Wind: Light and Steady from the SE
 Blowing Snow: Prev Snow Available for Transport: Small amounts
 Comments: Snow increasing throughout the day: At 1000 S2 snowfall increasing to S5 by 1330. Not much gusting wind on the ridge tops, visible wind affect both to the SE and NW indicating recent wind direction changes. Off of the ridges the wind was a steady light breeze without much evidence of mobile snow
AVALANCHE OBSERVATIONS
None Reported
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Deep Persistent Slab

Layer/Depth:
Base to 10cm above

Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Widespread
Where did you find this problem?
  Primary Concern Comments: Depth hoar persistent at bottom 10cm of snowpack. Touchy, widespread.
 
Avalanche Characteristics
Character/Avalanche Problem:
Storm Slab

Layer/Depth:
14cm from surface

Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Specific
Where did you find this problem?
  Problem 2 Comments: Touchy transition layer 14cm below surface - Fist to 4F density change
STABILITY TESTS
 Stability Test Results: Reproducible CTE, Q1 at 14cm from surface and CTE Q1 on persistent depth hoar.
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (widespread)    
 Collapsing (widespread)    
 Comments: Widespread cracking, collapsing and whumpfing while skinning. Shooting cracks travelling from collapse widespread, several slopes with cracks shooting across entire length. One instance of remote triggered collapsing on intermediate density tree slope 25 degree angle, NW facing. Ski cut on 25 degree slope, NW facing, 8950ft elevation, produced congruent, propagated crack across entire slope both sides of entry point of ski cut. No slide triggered.
SNOW STABILITY
 Snow Stability Rating for your observed area: Very Poor Confidence: HIGH Trend: Worsening
 Comments (aspects and elevations of instability, etc): With the amount of snow-fall experienced today, the expected forecast for continued snowfall, and the hair-trigger sensitivity of the existing snowpack on the ball-bearings at the base, it seems likely that this storm is going to only capitalize on the insecurity of the snowpack at this point. Depending on wind effect throughout this storm and the night, loading and scouring could set up additional triggers, though comment on this would be un-educated.
BOTTOM LINE
 Comments: This was a sketchy snowpack. Any slope in avalanche terrain W-NE, I will be extremely hesitant, if willing at all, to travel in following this storm until further observations can be made.