Close
PROFESSIONAL OBSERVATION FORM
 Start Date: 02.24.19 Name: VandenBos, Rand Operation: SAC
 Drainage/Route:  Spring-Cherry divide Observed Terrain:  7,100-8,800' Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: HST: 25cm Sky: X Precip: S2 Temps:
 Ridgeline Wind:
 Blowing Snow: Snow Available for Transport:
 Comments: 15cm new by 10am, another 10cm by 3pm. Snowing pretty steady S2 all day. Intermittent winds out of the SW, occasionally digging down to highway level. Temperatures were warming slightly, this afternoon's snow was a bit denser than the snow that fell last night.
AVALANCHE OBSERVATIONS
None Reported
 Comments: None observed, terrible visibility
SNOWPACK OBSERVATIONS
 HS: 120cm, SW-aspect at 8,800' 
 Upper Pack: 20cm PP on 40cm DF 
 Middle Pack: A few P MFcrs interspersed with generally rounded but poorly aggregated grains 
 Lower Pack: 40cm DH. Moist to wet at ground, still bone dry higher up where 2cm chains of 3-4mm grains are present.  
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Deep Persistent Slab

Layer/Depth:
100cm

Likelihood of Triggering
Sensitivity:


Spatial Distribution:
Widespread
Terrain
  Primary Concern Comments: 
 
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:


Likelihood of Triggering
Sensitivity:


Spatial Distribution:

Terrain
  Problem 2 Comments: Did not directly encounter, would have been primary concern if we'd been traveling in wind loaded terrain
STABILITY TESTS
 Stability Test Results: ECTX and ECTP26 down 100cm. CPST 23 and 28/100 END down 100cm. PST 27 and 33/100 END down 100cm. CPST 43/100 END down 60cm, PST 47/100 END down 60cm. All in location described above.
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated)    
 Comments: Very minor cracking in density inverted snow that fell during the day.
SNOW STABILITY
 Snow Stability Rating for your observed area: Fair Confidence: Trend: Worsening
BOTTOM LINE
 Comments: Not enough of a load to be making things too terribly spicy...yet. Would not have been tangling with wind slabs in complex, steeper terrain. New/old interface wasn't presenting obvious signs of instability, but there isn't a slab of any sort sitting on it yet. Suspect this problem will be touchiest in solar terrain with FC on thin MFcr, though the freshly buried surface was showing a decent bit of faceting prior to burial. No results with ECTs and CTs on 2/2, though PST and CPST done below the crust in loose grains produced propagation to end with cut lengths in the 40s. ECTX and ECTP 26 down 100cm (DH), PST and CPST cut lengths in the low 20's to low 30's continue to indicate that DH is worth continuing to pay attention to in thinner snowpacks in the S/B.