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PROFESSIONAL OBSERVATION FORM
 Start Date: 12.07.18 End Date: 12.07.18 Name: Davis Operation: SAC
 Drainage/Route:  Miller Ridge, N. Fork Soldier Creek Observed Terrain:  All aspects at middle and lower elevations Zone/Region:  Soldier Mountains
WEATHER OBSERVATIONS
 HN24: 0 HST: 0 Sky: FEW Precip: Temps: 25
 Ridgeline Wind: Calm
 Blowing Snow: Snow Available for Transport: Small amounts
 Comments: Zero near Fairfield and steadily warmer above. Clear to start the day with some increasing clouds from the SW by 1400.
AVALANCHE OBSERVATIONS
None Reported
 Comments: Observed half covered debris piles in the "Lunch Box" near Smoky Dome and other steep chutes along the Soldier Mountain Crest. All above treeline.
SNOWPACK OBSERVATIONS
 HS: 7000-8000' 25-45cm (deeper on Norths) 
 Upper Pack: (11/27-12/3) recent snowfall is faceting (F) and makes up the upper half of the pack 
 Middle Pack: (11/22-11/24) Thanksgiving snowfall is still relatively strong 4F to 1F+ making up the bottom half of the pack 
 Lower Pack: (Oct.-Early Nov) A depth hoar layer 5-10 cm thick was observed as low as 7,200' on NNW-N-NNE but was not present on SW-S-SE as high as 7,500' (and likely higher). 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
35-40cm

Likelihood of Triggering
Sensitivity:
Reactive

Spatial Distribution:
Widespread
Terrain
  Primary Concern Comments: DH was reactive in all snowpack tests. I only observed terrain up to 8,000' but I'd expect the problem distribution to spread to due W and East aspects by upper elevations. I seem to recall bare dirt near mountain tops on SW-S-SE before Thanksgiving.
 Comments: Persistent Slab problem is distributed where there was a decent amount of snow prior to Thanksgiving. The upper 15 cm of snow has quickly faceted but the lower 15 cm above the depth hoar was still stiff enough to propagate fractures in all formal and informal tests. Surface hoar was widespread on all aspects from 3mm to up to 2cm.
STABILITY TESTS
 Stability Test Results: 8,000' NNE: CT12, ECTP6, PST 30/90 END, SC dwn 32 on DH sz 4-5 (all performed twice).
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: MODERATE Trend: Steady
BOTTOM LINE
 Comments: As Chris mentioned in one of our general snow products, if it's "rideable" or in this area generally >40 cm then there is DH at the base but I didn't find it as concerning here as the observations from Mores Creek, Pioneers, and Galena Summit. Nonetheless it appears we will have a persistent slab problem from about 8,000' and up on all but SW-S-SE aspects and maybe a tad lower than 8,000' on shaded slopes.
FILE ATTACHMENTS

181207_SaltBowns_HighMarks_SE_8200.jpg
There were very few off trail tracks. These were on SE-facing terrain at 8200'.

181207_SaltBowns_N_7500.jpg
Snow cover on north facing terrain at ~7500'.

181207_SaltBowns_SH.jpg
Surface hoar up to 2 cm was found on most aspects.