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PROFESSIONAL OBSERVATION FORM
 Start Date: 12.17.16 Name: Davis Operation: SAC
 Drainage/Route:  Highway Obs Observed Terrain:  6,800-10,000', N-E-S Zone/Region:  Sawtooth Mountains
WEATHER OBSERVATIONS
 HN24: 0-2 HST: 20-25 Sky: VAR Precip: Temps: -14 to -22F
 Ridgeline Wind: Moderate from the NW
 Blowing Snow: L Snow Available for Transport:
 Comments: Cloudier in the WRV than it was north to Galena Summit and Banner. High clouds but good vis and filtered sun.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 12 Stanley Area Within past week 1 WL N 7,500' All aspects, rain on snow. Rain runnels also visible.
 1 2 Peaks South of Copper Within past week 3 SS N SE 8,800' ~1,500' wide, ~2-3' deep.
 1 McGown Peak Within past week 3 HS N E 9,500' Ridge between Mystery and McGown. ~500' wide, ~3-4' deep.
 2 Heyburn Ridge Within past week 2 HS N SE 9,000' Likely wind slab, ~200' wide in steep terrain.
 2 Thompson Peak Within past week 2 HS N SE 9,000' Located under rock bands and rolls mid-cirque.
 1 Old Decker Peak Within past week 3 HS N SE 9,700' Two high points lookers right of Old Decker. ~350' wide, ~3-5' deep. (photo)
 1 Head of Beaver Creek Within past week 2 SS NC NE 9,300' Appeared to be triggered by cornice fall.
 2 Cabin Creek Within past week 2 SS N E 9,300'
 1 Frenchmans Within past week 1 SS N E 9,000' Couple L in there as well.
 1 McDonald Peak Moraine Within past week 1 SS N SE 7,900' Looked like a pocket of persistent slab similar to those noted during the previous storm.
 Comments: All reported slides were from this weekend's storm. A few deeper crowns were still visible from the previous storm but are not listed above. Larger slides were in wind-loaded areas on the spine of the Sawtooths.
STABILITY TESTS
 Stability Test Results:
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
BOTTOM LINE
 Comments: Activity this cycle appeared to be less widespread and more focused in wind-loaded areas of the alpine.
FILE ATTACHMENTS

161217_NearOldDecker_SE_9700.jpg
Slab avalanche north of Old Decker Peak.