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PROFESSIONAL OBSERVATION FORM
 Start Date: 01.07.19 Name: Davis, Preuss Operation: SAC
 Drainage/Route:  Roadside Obs from Hailey to Galena Pass Observed Terrain:   Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: 10-16 HST: 12-24 Sky: FEW Precip: Temps:
 Ridgeline Wind: Strong and Steady from the W
 Blowing Snow: I Snow Available for Transport: Large amounts
 Comments: Plumes of snow streaming from high peaks in the Boulders and Smokys between 1100 and 1600. Wind affect was evident at middle elevations as well.
AVALANCHE OBSERVATIONS
None Reported
 Comments: I saw several avalanches that appeared to fail predominantly at the new old interface and at least a couple that looked to fail on deeper weak layers (N. side of Saviors, and Unknown Peak in N. Boulders east of Gladiator).
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:


Likelihood of Triggering
Sensitivity:


Spatial Distribution:

Terrain
  Primary Concern Comments: Based on observed avalanche activity.
 
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:


Likelihood of Triggering
Sensitivity:


Spatial Distribution:

Terrain
  Problem 2 Comments: Forecasted distribution. Some slides were in areas will little to no obvious wind affect. At least 2 looked to pull into layers deeper than the new/old interface.
STABILITY TESTS
 Stability Test Results:
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
BOTTOM LINE
 Comments: We saw avalanches involving the new snow in obviously wind loaded terrain and relatively sheltered terrain around Ketchum, in the N. Fork of the Big Wood in the northern Boulders and along both sides of the Smoky Mountain Crest. I suspect most of the activity was related to some amount of wind affect and i'm curious how the new/old interface will act as the storm slab settles. We did observe at least two slides that appear to have run on deeper weak layers.
FILE ATTACHMENTS

190107_CoyoteCreek_SoftSlab_SE_9500.jpg
Slab avalanche at the head of Coyote Creek in the Smoky Mountains.

190107_GalenaPass_Wind.jpg
Wind whipping the snow around at Galena Pass. This was a common sight in many exposed middle and upper elevation slopes.

190107_GalenaPk_NW_10500.jpg
Slides in the NW bowl of Galena Peak at ~10,500'. There was also a debris pile to the lookers left of this image that looked to have ran earlier in the storm.

190107_GladiatorPk_Slab_W_10200_2.jpg
Head on view of the Gladiator slide. West aspect at 10,200' in the Boulder Mountains.

190107_GladiatorPk_Slab_W_10200.jpg
Side view of the Gladiator slide. West aspect at 10,200' in the Boulder Mountains.

190107_HWY75_Slab_PlowTrigger.jpg
Plow triggered slab along HWY 75 south of Galena Pass. Triggered midday today (1/7).

190107_NorthBldrs_PersSlab.jpg
Thick slab at ~10500' on an unknown peak above Grand Prize Gulch in the Boulders.

190107_WRV_WindSlab_ENE_5900.jpg
Wind slab above Golden Eagle near the mouth of Greenhorn Gulch in the WRV. Northeast aspect at 5900'.