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PROFESSIONAL OBSERVATION FORM
 Start Date: 03.08.19 Name: Lundy Operation: SAC
 Drainage/Route:  Mushroom Ridge Observed Terrain:  7600-9400', SE-E-SW Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: HST: 25cm Sky: BKN Precip: Temps:
 Ridgeline Wind: Light from the SW
 Blowing Snow: None Snow Available for Transport: Large amounts
 Comments: While there were brief spells of sun, cloud cover most of the day kept things pretty cool. Solars took a little heat but only enough to have a very thin crust tomorrow at most.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 Several McDonald area Yesterday 1.5 SS N NE 9800 several thin crowns, at least one was fairly wide. See photo
 2-3 knob near Governors Punchbowl Yesterday 1 SS N E 8700 Thin slabs in relatively sheltered, mid elevation terrain. See photo
 Comments: Saw possible evidence of other small, recent slides similar to those listed above but not enough light or too far away to make out details.
SNOWPACK OBSERVATIONS
 HS: 8700, E: HS = 250cm 
 Upper Pack: 3/6 layer was 23-25cm down in sheltered terrain.
E: no MFcr present at 3/6 I.F. but a layer of FCsf exists
SE and SW: 1cm soft MFcr present at 3/6 I.F. PP (needles) right above the crust are faceted (see photo) 
 Middle Pack: No evidence of 2/23 layer in pit on E at 8700'. 2/2 layer was 150cm deep. 
 Lower Pack: n/o 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
25cm

Likelihood of Triggering
Sensitivity:
Unreactive

Spatial Distribution:
Specific
Terrain
  Primary Concern Comments: Insufficient slab to be a widespread problem. Would need an area with more HST or some wind effect.
 
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:


Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Isolated
Terrain
  Problem 2 Comments: Wind slabs along Mushroom ridge were small and unreactive
STABILITY TESTS
 Stability Test Results: ECTN's on the 3/6 layer on both E and SW. Hand shears were able to get planar results on SW and SE where a crust exists, but not on E where there was no crust.

Also, ECTX in the top 120cm on E at 8700'. The 2/23 I.F. would have existed somewhere in this area.
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
BOTTOM LINE
 Comments: Went out to look at the 3/6 interface on solar aspects. While a weak layer exists there - either FCsf on E or MFcr with a very thin layer of faceted PP above on SW and SE - in this area there was insufficient slab in sheltered terrain. Based on the natural avalanche activity on this layer, some areas (even in semi-sheltered terrain) have or had a sufficient after the 3/6 storm ended. The 3/6 layer seems thin, not well-developed, and unlikely to persist.
FILE ATTACHMENTS

190308_mcdonald.jpg
Thin slabs on McDonald Peak, ENE, 9800'

190308_gov_punchbowl.jpg
Thin slabs in semi-sheltered terrain near the Governors Punchbowl, E, 8700;

190308_FCsf_SW_9000.jpg
Faceted needle precip particles right above the 3/6 crust. SW, 9000'