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PROFESSIONAL OBSERVATION FORM
 Start Date: 12.19.18 Name: Savage Operation: SAC
 Drainage/Route:  glassing Ketchum-Galena Summit Observed Terrain:   Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: 5cm? HST: 15-30cm Sky: FEW Precip: Temps: 20s F
 Ridgeline Wind: Moderate from the NW
 Blowing Snow: L Snow Available for Transport: Large amounts
 Comments: Winds still sifting some snow over high alpine ridges at 1500hrs, but most of the transported snow appeared to be sublimating.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
  Galena Peak Today 3.5 U N W alpine Slide occurred between 10am and 1pm. Just under 1 mile wide, ran over 2000' vertical. Involved S-SW-W-NW aspects. Ben will have more details.
  Murdoch Ck Today 2 U N SW 9800'
 3 Silver Peak Today 1.5 U N SW 10400'
 2 Eagle Ck headwaters Today 2 U N W 9600'
  Parks Peak Today 2 U N SE alpine
 Comments: Impressive propagation/width on the Galena Peak avalanche, even in the absence of a thick+stiff slab. The slab was only an estimated 1-2 feet thick at the crown.
STABILITY TESTS
 Stability Test Results:
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
BOTTOM LINE
 Comments: Activity from last night and today appeared to involve primarily the crust+facet and facet layers buried on 12/11 or 12/16 and possibly involved the 11/22 Thanksgiving weak layer (old depth hoar). We're far from out of the woods yet with any of the weak layers in question. Heads up as we continue the incremental/cumulative loading we've been seeing - the Galena slide may be a preview of what's to come, or it may be an outlier. I'm guessing it's not the last big event we see this season, and those are the kinds of events that catch professionals and experienced recreationists.
FILE ATTACHMENTS

181219_GalenaPkSWBowl_headon_resized.jpg
Galena Peak slide head on view

181219_GalenaPkSWBowl_resized.jpg
Galena Peak slide from Alexander Ross pullout

181219_EagleCk_headwaters_resized.jpg
Eagle Ck headwaters activity