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PROFESSIONAL OBSERVATION FORM
 Start Date: 12.23.17 Name: VandenBos Operation: SAC
 Drainage/Route:  Williams Peak east shoulder Observed Terrain:  6,400-9,400' Zone/Region:  Sawtooth Mountains
WEATHER OBSERVATIONS
 HN24: HST: 40-45cm Sky: Precip: Temps:
 Ridgeline Wind: Light from the N
 Blowing Snow: L Snow Available for Transport: Large amounts
 Comments: Skies cleared from the north starting around noon. 15cm at the highway, 40-45cm up high, totals from 12/22-12/23. Light northerly winds increasing late in the day were easily transporting snow.
AVALANCHE OBSERVATIONS
None Reported
 Comments: I didn't really get a good chance to look in detail at upper elevation terrain today, thanks to the poor visibility in the morning. When visibility improved I saw lots of dry loose in steep terrain and quite a few small slabs in upper elevation terrain that had been wind loaded, mostly the sort of things that you'd expect to see. I did see two slabs around ~9,000' on a NE aspect that were a bit surprising, probably more of a persistent weak layer issue than a wind slab issue.
AVALANCHE PROBLEM ASSESSMENT
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STABILITY TESTS
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SNOW STABILITY
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 Comments (aspects and elevations of instability, etc): Felt like a comfortable moderate in non-wind effected middle elevations where I was skiing, but considerable for upper elevations seemed appropriate for the day. If the wind picks up much there is quite a bit of very low density snow around for transport and slabs will likely be forming quickly.
FILE ATTACHMENTS

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SSE face Williams, dry loose and small wind slabs

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SSE face Williams

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Marshall wind slab