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PROFESSIONAL OBSERVATION FORM
 Start Date: 02.13.19 Name: Savage and McCormick Operation: SAC
 Drainage/Route:  Couch Summit Rd - Owens Ck Observed Terrain:  several aspects to 6500' Zone/Region:  Soldier Mountains
WEATHER OBSERVATIONS
 HN24: 20cm HST: ? Sky: X Precip: S2 Temps: 28 F
 Ridgeline Wind: Light and Steady from the SE
 Blowing Snow: L Snow Available for Transport: Large amounts
 Comments: Terrible visibility, like the inside of a ping pong ball. It snowed about 15 cm (6") overnight and then 2-3" in the few hours we were out. Wind observations only apply to lower elevations.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
  Couch Summit road cut Today 1 SS ASu SE 6200'
 Comments: I skied off a roadcut (couldn't see it) and triggered a 50' wide, super soft slab. Terrain was inconsequential, but impressive width for how soft the slab was (4F). 40 degree road cut, 15-20cm 4F slab, just the new snow since it started snowing last night. We triggered another tiny little road cut with sleds on the way up, undercutting the bank - it released about 10-15' above the road and sled track.
SNOWPACK OBSERVATIONS
 HS: 50-120cm (just at lower elevations) 
 Upper Pack: 15-25cm new snow from last night and today, then about 15-70cm recent storm snow 
 Middle Pack: frozen crusts and melt freeze crystals (hard layers): Feb 2 crust prominent on all aspects below 6500 ft: some isolated places had hard slabs that formed during the last big NW wind event on Feb 10 
 Lower Pack: mostly frozen crusts and facets/DH that had been wet and undergone some melt-freeze metamorphosis (hard layers) 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Storm Slab

Layer/Depth:
15-25cm

Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Widespread
Terrain
  Primary Concern Comments: Not sure if it was cold enough to produce this problem at middle and upper elevations - yet.
 Comments: Wind slabs would have been the primary problem up another 2000' in elevation.
STABILITY TESTS
 Stability Test Results: No formal tests performed, just lots of hand tests.
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (widespread) Depth: 15-25cm Length: 1-3 ft
 Collapsing (isolated) Depth: 15-60(?) cm Length: 30 ft
SNOW STABILITY
 Snow Stability Rating for your observed area: Fair Confidence: HIGH Trend: Worsening
 Comments (aspects and elevations of instability, etc): The storm slab problem was only an issue on very steep slopes (near 40 degrees) by 2 PM today.
BOTTOM LINE
 Comments: With the relatively warm temperatures, I expect the storm slabs to become more sensitive and wider as they grown in thickness. They are sitting above delicate, low-density snow from recent storms, making them touchy. I'd expect to be able to trigger significantly larger and wider slides in less-steep terrain by tomorrow afternoon. The visibility definitely complicated issues today. I couldn't see the steep roadcut at the bottom of the mellow slope and skied off it accidentally, producing a full-on yard sale and triggering an insignificant little slide. After seeing me disappear, my partner skied down and promptly skied off the same road cut by accident. Quite a show. We were in very simple terrain, so there were no consequences. Travel would have been rough and dangerous in more complex, larger avalanche terrain.
FILE ATTACHMENTS

190213_Couch_roadcut_ASu.jpg
Examining the crown of the little yard-sale/ski triggered slide. D1, SE, 6200', 8" thick, 4F slab involving the new snow since about 7PM yesterday when it started snowing again.