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PROFESSIONAL OBSERVATION FORM
 Start Date: 02.15.19 Name: Lundy Operation: SAC
 Drainage/Route:  Copper Mountain Observed Terrain:  6900-8900' Zone/Region:  Banner Summit
WEATHER OBSERVATIONS
 HN24: 40cm HST: Lots Sky: X Precip: S2 Temps:
 Ridgeline Wind: Moderate and Gusty from the SW
 Blowing Snow: I Snow Available for Transport: Large amounts
 Comments: 40cm on yesterday's skin track at the highway elevation. Winds were M with periods of S, even at mid elevations. Lots of snow being moved, our skintrack at mid elevations was partially filled in at the end of the day. S1-S2 all day with periods of more intense precip. 7cm new snow from 11am to 4pm. Ski pen on sheltered slopes was 60-80cm
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 ~2 Copper North Side Today 1.5 SS N NE 8900 At least 2 wind/storm slabs in ~40* actively loading terrain, looked to be 20-30cm deep. Poor visibility and couldn't make out many details.
SNOWPACK OBSERVATIONS
 HS: 200cm at highway, 275cm on W @8200'. Obs below from pit on W @8200' 
 Upper Pack: 135cm of settled storm snow on the 2/2 interface. 1F at base of this layer. Generally right side up storm snow.  
 Middle Pack: n/o 
 Lower Pack: only probed...bottom 15cm or so felt weaker 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
30-90cm

Likelihood of Triggering
Sensitivity:
Reactive

Spatial Distribution:
Specific
Terrain
  Primary Concern Comments: Problem much more pronounced at upper elevations, but some sizeable drifts exist at mid elevations. I was able to stomp a small wind slab at the top of copper that broke 20-30cm deep.
 Comments: The deep slab problem here is now down 200-250cm. When the storm clears we'll see if anything pulled out deeper, but I think the deep slab problem is off the table for the time being.

At lower elevations, yesterday's warming caused a density inversion about 50cm down and this was producing easy hand shears, but I didn't see any activity on the steeper slopes above the valley floors.
STABILITY TESTS
 Stability Test Results: 8200', W: Performed an ECT on the snow above and including the 2/2 I.F. A few unimpressive ECTNs in the top 60cm but no propagating results.
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated)    
 Comments: Cracking was isolated to wind slabs on the ridge crest
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
 Comments (aspects and elevations of instability, etc): Greatest danger is on steep, wind loaded slopes