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PROFESSIONAL OBSERVATION FORM
 Start Date: 02.11.19 Name: Davis, VandenBos Operation: SAC
 Drainage/Route:  Baker Creek Observed Terrain:  7900-9700, S-SE-E Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: HST: 70 cm Sky: OVC Precip: S-1 Temps:
 Ridgeline Wind: Moderate and Steady from the W
 Blowing Snow: Snow Available for Transport: Large amounts
 Comments: Steady wind-loading from the WSW for much of the tour at middle and upper elevations.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 1-2 Peak Directly Across from Norton Ck on the S. side of Baker Ck Within past week 2 NW 8,900 Visibility was poor, but a good size crown sat under the rocks in the wind-loaded upper start zone.
 5 Baker Ck Within past week 1 N S 7,200 We saw a handful of very small storm slabs along Baker Ck Road in steeper rocky sections. They appeared to go on a mid-storm layer.
 1 Peak NE of Baker Lake Today 1 SS AS NE 9,300 Stomping along a cornice triggered a 40' wide wind slab that picked up speed quickly. Ran about 250' (confined by terrain).
 Comments: Generally, the visibility was poor due to grey skies and blowing snow at middle and upper elevations.
SNOWPACK OBSERVATIONS
 HS: 150-170 on South, and 190 on NE @ ~9,000' 
 Upper Pack: 70 cm HST 
 Middle Pack:  
 Lower Pack: 20-30 cm of DH/FC that look to be getting squashed and gaining a little strength, although still 4F. This was the strongest basal layer I'd seen in a while outside of those that have seen meltwater.  
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
40-100 cm

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:

Terrain
  Primary Concern Comments: Wind slabs were growing rapidly on this tour but remained mostly 4F or softer and took quite a bit of encouragement to get moving. Fresh slabs were mainly on E and NE with today's wind, but are likely on many aspects after S wind during the bulk of the storm.
 
Avalanche Characteristics
Character/Avalanche Problem:
Deep Persistent Slab

Layer/Depth:
150-200 cm

Likelihood of Triggering
Sensitivity:
Not Observed

Spatial Distribution:
Widespread
Terrain
  Problem 2 Comments: Basal weak layer is now 150+ in this area that has been one of the shallower areas of the SKY/BLDR zone this season.
STABILITY TESTS
 Stability Test Results:
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated) Depth: 40 cm Length: 200 cm
 Comments: Some cracking in fresh wind slab along an exposed ridge.
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: HIGH Trend: Steady
 Comments (aspects and elevations of instability, etc): HIGH at upper elevation with a more widespread wind slab problem seemed reasonable given the intense loading and large amounts of snow avaialble to move around. CON at mid, MOD at lower.
BOTTOM LINE
 Comments: Given the loading, it wouldn't have surprised me to see a natural or two in steeper terrain at upper elevation today. With S and W wind events moving this snow around we now have a fairly widespread layer of wind slab to deal with that should tie things together a bit more as we build a meatier slab in the next few days.