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PROFESSIONAL OBSERVATION FORM
 Start Date: 03.06.19 Name: Davis Operation: SAC
 Drainage/Route:  Wells Peak Observed Terrain:  5400-8000, All Zone/Region:  Soldier Mountains
WEATHER OBSERVATIONS
 HN24: 5-20 cm HST: 5-20 cm Sky: VAR Precip: S1 Temps:
 Ridgeline Wind: Light from the S
 Blowing Snow: L Snow Available for Transport: Large amounts
 Comments: Cloud ceiling lowered and intermittent S1 snow began around 1200. Wind also increased from calm to light to moderate from the south. Light blowing snow was filling in sled tracks along ridges.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 2 Brush Canyon Within past week 1.5 SS N W 7000' This looked relatively fresh.
 Comments: A few baby wind slabs below cornices lee to SW and W wind.
SNOWPACK OBSERVATIONS
 HS: I dug on NNW (240 cm) and SSW (120 cm) aspects on Wells Peak at 8,000'. The north aspect was much fatter, but I was not in an obviously wind-loaded area. The south aspect was subject to scouring throughout these south-flow storms but was well below ridgeline. Generally speaking, the north was deep and strong (mostly 1F) with a massive mid-pack slab composed of February snows. Weak layers were present, but hard to discern and produced no interesting results. The info below pertains to the more reactive SSW.  
 Upper Pack: SSW: 5 cm new snow over a MFcr with FC under it. This layer will not behave well unless it improves before the next substantial load.  
 Middle Pack: SSW: (2/2) MFcr was down 65 cm and had well defined FC on the underside.  
 Lower Pack: SSW: The lower 50 cm was two weak layers of FC (4F) and DH (F). 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
65 cm (2/2), 100 cm basal FC/DH

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Widespread
Terrain
  Primary Concern Comments: Both (2/2) and the basal FC/DH produced results in snowpack tests. The basal FC/DH were the most concerning in this location. These same layers were present but hard to discern on norths and produced no results.
 
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
40 cm

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Specific
Terrain
  Problem 2 Comments: More of a developing problem than a concern today. 4F to 1F- fresh wind slabs formed last night and later in the afternoon today. I saw a few fresh baby D1 slab failures right below cornices.
STABILITY TESTS
 Stability Test Results:
NNW:
ECTX in upper 125 cm, CPST (x2) with no results on FC layers in upper 80 cm.

SSW:
CT6 SC down 10 under MFcr, ECTP26, PST 35/100 END, CPST 25/100 END on basal FC/DH, PST 50/100 END, CPST 50/100 END under (2/2) MFcr down 65 cm
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated) Depth: 40 cm  
 Comments: Small cracks in fresh 4F wind slab
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
 Comments (aspects and elevations of instability, etc): Fair stability on souths, very good on norths.
BOTTOM LINE
 Comments: Similar to yesterday in Lake Creek I found weak layers to be more pronounced and touchier on south-facing slopes than on adjacent north-facing terrain. These windward south-facing slopes are also thinner allowing easier access to weak layers with a sled or skis. Weak layers as deep as 2/2 and below on norths are under a fat, stiff slab and seem squashed and hard to locate.
FILE ATTACHMENTS

190306_WellsSummit_01.jpg
Small recent persistent slab on a west aspect at 7,000' in Brush Canyon.