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PROFESSIONAL OBSERVATION FORM
 Start Date: 02.21.18 Name: Savage Operation: SAC
 Drainage/Route:  Galena Summit - roadside Observed Terrain:  8700-8850', generally SE and E/SE Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: trace? HST: 13-60cm Sky: X Precip: S-1 Temps: 11F
 Ridgeline Wind: Light
 Blowing Snow: Snow Available for Transport: Small amounts
AVALANCHE OBSERVATIONS
None Reported
 Comments: Investigated Verlons slide (appeared to be plow triggered at top of pass, D1, minimal) and slide on slope immediately north of Galena Summit parking area (D1.5 or 2, 6-20" thick crown)
SNOWPACK OBSERVATIONS
 HS: Verlons 70-75cm...100-120cm on N side of parking area (see attached profile for SE Verlons 8750') 
 Upper Pack: Verlons: 5cm PP, thin razor rain or sun or temp crust, then 10cm PP/DF, then .5-1cm FCnearsurface sitting above a stout 5cm thick crust (crust likely formed Feb 5-9)
East side of pass: 15-50cm dense wind slab sitting on prominent + stout + dirty crust  
 Middle Pack: Verlons: well developed depth hoar/facets and degrading crusts
east side of road=not observed 
 Lower Pack: Verlons: mostly large, well developed depth hoar 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
recent snow 15-60cm

Likelihood of Triggering
Sensitivity:
Not Observed

Spatial Distribution:
Widespread
Terrain
  Primary Concern Comments: The slide on the E side of the road also stepped down into some older layers of snow (evidence-the slab/debris had dirty layers of snow in it).
 Comments: Calling it a persistent slab problem because of the 2/14 FC above a crust. Verlons slide may have been gently wind loaded but was pretty shallow and a very low density slab.
STABILITY TESTS
 Stability Test Results: None performed.
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
BOTTOM LINE
 Comments: The couple recent avalanches I observed at the top of Galena Summit ran on a thin layer of small faceted crystals (FC) sitting on a crust that formed during the rain/hot weather from Feb 5-9. The FC were probably buried on Valentines Day and will likely misbehave again with the next storm/loading event, especially where only about 6-8" of low density snow is currently above the FC. If we ever get a big storm, deeper faceted layers will be suspect where the snowpack is thin (like the Verlons path next to the road).
FILE ATTACHMENTS

180221_Verlons_pit_crownprofile.jpg
Snowpit dug on Verlons path just above road at top of Galena Summit.

180221_Verlons_pit_label.jpg
Photo of Verlons pit