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PROFESSIONAL OBSERVATION FORM
 Start Date: 01.09.17 End Date: 01.09.17 Name: Davis Operation: SAC
 Drainage/Route:  South Valley - Roadside Observed Terrain:  5300-9000, All aspects Zone/Region:  Wood River Valley
WEATHER OBSERVATIONS
 HN24: 40 cm HST: 50 cm Sky: OVC Precip: Temps: 35 F
 Ridgeline Wind:
 Blowing Snow: Snow Available for Transport:
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 15 South of East Fork Today 2 SS N All aspects, elevations up to 7,000. Mix of size 1-2.
 5 East Fork to Ketchum Today 1 SS N All aspects, elevations to 6,500.
 1 Della Today 2.5 SS N E 7,200' Pushing size 3 based on debris. At least three distinct crowns. Largest is 800' wide and 1,400' long. Blocked river in several spots.
 Comments: Larger slides were noted south of East Fork, likely due to heavier wet snow and light rain. Slides north of East Fork were narrower and looked shallower as well. Slides hit Warm Springs, Sage road in Ketchum, Croy Canyon near the animal shelter (last night around 730 pm) and possibly Greenhorn.
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Storm Slab

Layer/Depth:
30-45 cm

Likelihood of Triggering
Sensitivity:
Very Touchy

Spatial Distribution:
Widespread
Terrain
  Primary Concern Comments: More prevalent south of East Fork. Limited Obs.
 Comments: Releases in Ketchum were after the cold front and uptick in wind and snow. Scott should have more info and pictures later.
STABILITY TESTS
 Stability Test Results:
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
FILE ATTACHMENTS

170109_Carbonate_000.jpg
Natural soft slab off the shoulder of Carbonate at the mouth of Croy Canyon.

170109_Elkhorn.jpg
Steep north-face near Elkhorn.

170109_Della_000.jpg
Della lower shoulder. The whole face went but was obscured at the time of the picture.

170109_Carbonate_002.jpg
Storm slab failed at the new/old interface.