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PROFESSIONAL OBSERVATION FORM
 Start Date: 03.13.19 Name: Davis Operation: SAC
 Drainage/Route:  Mushroom Observed Terrain:  7600-9800', W-S-E Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: 2-5 cm HST: 2-5 cm Sky: VAR Precip: S-1 Temps:
 Ridgeline Wind: Moderate and Gusty from the NW
 Blowing Snow: M Snow Available for Transport: Small amounts
 Comments: In and out of mid-level clouds for the majority of the morning. Some drifting lee to local E wind along the lower portion of the ridge. Pluming was evident in portions of the Smokys and further south along the Boulders but nothing dramatic. Wind did seem to increase as I was exiting around 1300.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 1 Mushroom Ridge Today 1 SS ASc SE 9790' Pocket of fresh wind slab that formed overnight and this morning. Max crown depth of 45 cm that tapered quickly off of ridgetop.
SNOWPACK OBSERVATIONS
 HS: n/o 
 Upper Pack: 2-5 cm new snow sitting on a crust. Below that a matrix of recent crusts in the upper 40 cm on SW-S-SE. 
 Middle Pack: n/o 
 Lower Pack: n/o 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
20-45 cm

Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Specific
Terrain
  Primary Concern Comments: 
STABILITY TESTS
 Stability Test Results:
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Collapsing (isolated) Depth: 40 cm  
 Comments: Small collapses in wind-pillows along upper elevation ridgeline.
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
 Comments (aspects and elevations of instability, etc): LOW at middle and lower elevation.
BOTTOM LINE
 Comments: Wind slabs were isolated to near ridgetop in this location and could have been easily avoided, but in terrain with a more favorable fetch or greater HST these slabs would have posed a more legitimate hazard for folks traveling in the alpine.

Our next warm day should easily peel the 1-2" of new snow off anything steep and sunny. This snow all sits on a nice slippery crust. As wind slabs heal we are staring down the pipe rising temps and wet issues for a while.
FILE ATTACHMENTS

190313_Mushroom_02.jpg
Small slab triggered on ski cut.