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PROFESSIONAL OBSERVATION FORM
 Start Date: 12.30.18 Name: VandenBos Operation: SAC
 Drainage/Route:  Titus Ridge Observed Terrain:  8,700-10,000' Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: HST: 10cm Sky: VAR Precip: S1 Temps:
 Ridgeline Wind: Moderate and Intermittent from the NW
 Blowing Snow: L Snow Available for Transport: Small amounts
 Comments: Variably cloudy until mid-afternoon, then a nice squall blew through from ~1500-1545 dropping another cm of snow and blowing more snow around.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 2 Abe's Armchair Today 2 SE 9,500' Interesting crowns, in obviously wind loaded terrain but a little ways below the mid-slope feature. Deeper portions of crowns look to be at least 1.5-2' deep, maybe a touch deeper in spots. Debris doesn't look extra fresh, but may just be blown in. Looks like these may have started out as wind slabs and then failed on a layer deeper than the new/old interface. Photo attached.
 1 Roadside HS Today HS SE 8,200' Plow-triggered (?) HS on south side of Galena Pass, I haven't seen this previously and the crown looked pretty crisp despite being obscured by wind loading. Small vertical run but pushing 200' wide. See photo attached.
 1 Above Titus Creek HS NW 9,000' Above Titus Creek, not sure on timing.
 Comments: In addition to the avalanches listed above, observed a handful or two of small, mid-storm wind slabs near ridgelines/mid-slope cross-loaded terrain features.
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:


Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Specific
Terrain
  Primary Concern Comments: Primary concern based on likelihood of encountering, though I suspect that many places that you might trigger a wind slab would have a decent chance of stepping down into deeper persistent problems, or at least gouging into the facet stack below. Wind slabs found on slopes leeward to and cross-loaded by NW winds
 
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:


Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Widespread
Terrain
  Problem 2 Comments: 12/11 FC->DH. Aspect rose based on suspected distribution. Stubborn borderline unreactive based on pattern of activity, though I think that could change with a sufficient slab on top.
STABILITY TESTS
 Stability Test Results:
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
FILE ATTACHMENTS

P1150713.JPG
Galena Roadside HS

P1150763.JPG
Abe's Armchair

P1150766.JPG
Titus fresh cornices

P1150831-001.JPG
Pole Creek/Dry Creek Peak

P1150789.JPG
Cracking in fresh wind slabs

P1150837.JPG
Headwaters Germania Creek

P1150776.JPG
Mill Gulch?