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PROFESSIONAL OBSERVATION FORM
 Start Date: 04.05.19 Name: Savage Operation: SAC
 Drainage/Route:  Baker/Lost Shirt/Cunard/Castle/Thompson Cks Observed Terrain:  6600-9700', most apsects but few solars at lower elevations Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: 8-12cm HST: ? Sky: BKN Precip: S-1 Temps: 30s F
 Ridgeline Wind: Light and Intermittent from the W
 Blowing Snow: L Snow Available for Transport: Small amounts
 Comments: I was out from 2:30-6:30PM.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 1 Baker Ck Today 2 WS NL NW 8500 Accross the drainage from Norton Ck. Small wet loose triggered a pocket of wet slab which rode up quickly. Slide released between 3-6PM. See photo.
 1 Baker Ck Today 1 WL N NW 9000 Same face/cirque as slide above. See photo.
 1 Big Wood River Today 2 WL N NE 6500 Just upriver from Oregon Gulch, river right. Little blob off rocks gouged out steep, rocky path to the ground. See photo.
 1 Warm Springs Ck Today 2 WL N NW 6400 Board Ranch area, released around 5:45 according to report from Janet K. Appears to have flanked out as a wet slab part way down the path. See photo.
SNOWPACK OBSERVATIONS
 HS: 100-200cm (7600 to 9700') 
 Upper Pack: >8900'=wintery, dry new snow on frozen crusts of varying thicknesses (2-3mm on shady, about 1cm on solars), some graupel near top of new snow
8700-8900'= dense/damp new snow on frozen crust with moist snow for 5-15cm below upper crust
8400-8700'= transition to wetter upper pack regime: upper crusts were thicker (1-2cm) but weren't frozen solid - they were bending/breaking but not cleanly...still supportable on skis, but W-NW-N-NE were losing structure/support more than sunnier aspects...wet snow down about 15-20cm below surface at 8400'
7900-8400'= wet glop down about 20-30cm from surface, worst on shadier aspects
below 7900' = a hot mess. Wet at least 40cm down, and wet/moist/damp all the way to the ground on shadier aspects. Shady aspects had the worst structure at these elevations - sunnier slopes had a crust about 20cm down that was maintaining some stiffness.  
 Middle Pack: above 8900' = dry, hard (P) round grains
7900-8900' = varying degrees of wet/moist/damp (more free water as you descended)
below 7900'= wet snow with some crusts/frozen melt-freeze grains barely hanging in there to give some structure to the snowpack 
 Lower Pack: not observed except for below about 7900': there, it was wet/damp snow. Not supportable on sled or on foot except where lots of old tracks existed and even then it was marginal. Barely supportable on skis.  
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wet Loose

Layer/Depth:
20-40cm

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Specific
Terrain
  Primary Concern Comments: I couldn't get things to move when ski cutting/pushing on the top of 35-38* slopes, appeared to have to be steep (near 40*). But, I didn't get too far down into the paths - the chance of wet slabs and sizable wet loose slides kept me cautious.
 
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
10-20cm

Likelihood of Triggering
Sensitivity:
Not Observed

Spatial Distribution:

Terrain
  Problem 2 Comments: No wind slabs observed. Needed another 1000' of elevation to get into wind-transported snow if it exists in this area.
 Comments: I didn't separate wet slab as another problem, but it was on my mind on steep, W-NW-N-NW slopes below about 8400' and especially below 7900'.
STABILITY TESTS
 Stability Test Results: None performed.
SNOW STABILITY
 Snow Stability Rating for your observed area: Good Confidence: HIGH Trend:
 Comments (aspects and elevations of instability, etc): Shady, >38* slopes below about 8400' and especially below 7900' were concerning. From 8900-9700' where the snow was dry, the stability was very good.
BOTTOM LINE
 Comments: The spring transition is in full swing, working it's way up in elevation. The "sweet spot" today for instability/wet avalanche hazard in this area was W-NW-N-NE aspects between 6500-8400' and especially from 6500-7900'. I expect the elevation band of greatest concern to gradually move uphill in the coming days - there's too much free water and heat in the snowpack for short spells of below-freezing temperatures to do much more than delay the inevitable. Sunnier aspects at middle elevations have better structure/thicker crusts and will need to be monitored to see if they become worrisome or go out with a whimper as they transition to a summer snowpack.
FILE ATTACHMENTS

190405_BakerCk_WS_8500_NW_cropped.jpg
Baker Ck wet slab and wet loose, NW aspects. 8500' wet slab, 9000' wet loose.

190405_WarmSpringsCk_BoardRanch_6400NW_Kellam_545pm.jpg
Warm Springs Ck wet loose and wet slab (?) near Board Ranch, 6400' NW. Photo: J Kellam.

190405_WoodRiver_OregonGulch_WL_6500NE.jpg
Wood River WL just above Oregon Gulch, 6500' NE.