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PROFESSIONAL OBSERVATION FORM
 Start Date: 01.19.19 Name: Davis, VandenBos Operation: SAC
 Drainage/Route:  Spring/Cherry Creek Divide Observed Terrain:  7000-9300', West and South Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: 0-2 cm HST: 16 cm Sky: VAR Precip: Temps:
 Ridgeline Wind:
 Blowing Snow: Snow Available for Transport: Small amounts
 Comments: In and out of clouds. Snow fell at S1-2 for about half the tour with bursts of S3. Very little to no wind at this generally sheltered location. T-shirt climbing weather for a good bit early in the tour with moist dense snow at the surface.
AVALANCHE OBSERVATIONS
None Reported
 Comments: No new avalanche observations.
SNOWPACK OBSERVATIONS
 HS: 85 cm on SSW @ 9,300' 
 Upper Pack: 16 cm settled storm snow over a MFcr 
 Middle Pack: Faceted 4F+/1F- slab 
 Lower Pack: 20 cm of DH sz 4-5 mm 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
65 cm

Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Widespread
Terrain
  Primary Concern Comments: Stubborn in areas where the slab is weaker.
STABILITY TESTS
 Stability Test Results: SSW @ 9,300': ECTP15, CPST 26/100 End and PST 29/100 End dwn 65 cm on DH sz 4-5 mm. Out of curiosity and to help illustrate the problem to the public, we performed a couple non-standard mega-large block tests that resulted in slab fracture as well as propagating results.
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated)    
 Comments: We were both surprised at the lack of collapsing and cracking in areas with a stiffer (>1F) mid-pack slab.
SNOW STABILITY
 Snow Stability Rating for your observed area: Fair Confidence: MODERATE Trend: Steady
 Comments (aspects and elevations of instability, etc): MODERATE to LOW at low elevations with a more heavily faceted and thinner mid-pack slab.
BOTTOM LINE
 Comments: We traveled in <35 deg relatively sheltered (for the Boulders) terrain. Even in these areas, the slab was just strong enough to keep me from feeling comfortable entering steeper terrain. The basal facets and depth hoar are incredibly weak and well within the realm of human-triggering.