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PROFESSIONAL OBSERVATION FORM
 Start Date: 02.27.19 Name: Savage Operation: SAC
 Drainage/Route:  driving and glassing tour South Valley Observed Terrain:  several/most aspects, lower and middle elevations (marginal visibility) Zone/Region:  Wood River Valley
WEATHER OBSERVATIONS
 HN24: ? HST: ? Sky: BKN Precip: Temps: 30s F
 Ridgeline Wind:
 Blowing Snow: Prev Snow Available for Transport: Large amounts
 Comments: 1400-1530hrs. No wind transport at that time. Visibility was in and out with intermittent cloud decks around 8000'. Unknown recent snowfall due to rain and warm temperatures. Evidence (see Greenhorn Gulch photo) of significant rainfall below 6600'.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 1 Hyndman Ck Today 3 U N S 9400 S/SE face of the Peanut (Peak 9631) between N Fork Hyndman Ck and Hyndman Ck. 1000-1500 ft wide crown, estimated 2-4 ft thick. See photo.
 many WRV Today 1.5 SS N Dozens of fresh D1.5-2 surficial soft slab/wet slab slides in Wood River and surrounding drainages, releasing near and just above the rain line (6500-7000').
 1 Ohio Gulch Today 2 SS N S 7200 Persistent slab crown on long ridgeline on N side of Ohio Gulch, well above the dump and mine. May have been bigger than D2.
 1 Fisher Creek Today 2 SS N W 7300 Fisher Ck in Little Wood drainage. Persistent slab, may be bigger than D2.
 Comments: There was evidence of many (over 50) slides from last night and previous days, all D1-D2. I was not able to view upper elevations due to limited visibility.
SNOWPACK OBSERVATIONS
 HS: not observed 
 Upper Pack: Below 6300', upper 10cm (4inches) was wet from rain and warm temperatures. In layers below that, snow was moist/damp but without free water.
From 6300-6600', the surface was wet but free water penetration was not as deep.  
 Middle Pack: PP 
 Lower Pack: Not observed 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
50-100cm

Likelihood of Triggering
Sensitivity:
Reactive

Spatial Distribution:

Terrain
  Primary Concern Comments: Significant natural activity on W-SW-SE-S aspects in middle elevation terrain in the South Valley.
 
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
20-200cm

Likelihood of Triggering
Sensitivity:
Not Observed

Spatial Distribution:
Specific
Terrain
  Problem 2 Comments: Significant wind pillows and drifts in exposed terrain near ridges, including sub-ridges.
STABILITY TESTS
 Stability Test Results: None performed
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
BOTTOM LINE
 Comments: Limited visibility today, but widespread D1-D2 activity was focused near and immediately above the rain line (6500-7000') from East Fork/Greenhorn to the south. Dozens of fresh slides from early this morning and this afternoon when the sun popped out. Also evidence of dozens of slides that occurred in the previous 24-48 hrs and were blow in or obscured by additional snowfall. The Hyndman Ck slide was impressive in width - will be interesting to see what the debris pile looks like/how far and wide it ran. I'm guessing there is a lot more to be seen/discovered when we have better visibility on Friday and Saturday. The new drifts and wind features in Croy Canyon are impressive - I don't trust them at all right now.
FILE ATTACHMENTS

190227_HyndmanCk_persistentslab_9500ft_S_cropped.jpg
1000-1500ft wide, estimated 2-4 ft thick, persistent slab avalanche in Hyndman Ck drainage. Generally S aspect, released near 9500', probably ran about 2000' vertical.

190227_FisherGulch_Pios_persistentslabs_W_7200ft_cropped.jpg
Persistent slab at middle elevations in Fisher Ck northeast of Bellevue. 7200', W aspect.

190227_GreenhornGulch_rainrunnels.JPG
Rain runnels on S aspect in Greenhorn Gulch drainage. Top of slope is about 6700'.

190227_CroyCanyon_windloading.JPG
Obvious wind-loading in Croy Canyon. Large features formed since the last storms.