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PROFESSIONAL OBSERVATION FORM
 Start Date: 02.18.19 Name: Davis Operation: SAC
 Drainage/Route:  Couch Summit, Elk Ridge Observed Terrain:  6000-8000, S-W-N Zone/Region:  Soldier Mountains
WEATHER OBSERVATIONS
 HN24: HST: Sky: VAR Precip: Temps:
 Ridgeline Wind: Calm
 Blowing Snow: Prev Snow Available for Transport: Small amounts
 Comments: Lots of sun in the morning, increasing clouds midday and clearing again as I left around 1500. Very little wind, and no noticeable blowing snow at upper elevations.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 2 Soldier Creek/Phillips Within past week 2 N E 5800' Reported to have ran around the evening of the 13th or morning of 14th.
 1 Smoky Dome Within past week 3 HS N NE 9400' Estimated 600' wide, up to 15' deep, ran 500 vertical. Riders in the area estimate >20' deep debris piles in places.
 1 False Peak (north arm of Smoky Dome) Within past week 2 N E 9000' Sluff or cornice triggered slab in an apron.
 Comments: I had a good view into the Soldiers with relatively few slides to report. There did appear to be several smaller looking loose and wind slabs but much of that evidence would have been covered in the multi-day storm. I had mediocre light by the time I was able to look back toward the southern Smokys.
SNOWPACK OBSERVATIONS
 HS: 7,700' Souths 135 cm, Norths 170-180 cm 
 Upper Pack: 70-100 cm F to 1F+ snow since 2/2 
 Middle Pack: Souths: Multi-layer sandwich of K hard MFcr and rounding FC. 
 Lower Pack: Souths: FC that have seen a couple waves of meltwater, rounding and fairly strong @ 4F+, did not dig to ground on North.  
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
45-? cm

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Widespread
Terrain
  Primary Concern Comments: There were RP shears in the most recent wind slabs that formed at the tail end of the storm down ~45 cm but this interface already looks like it's healing quickly. Some slabs failed at the 2/2 (ECTP29) but this was also RP.
 
Avalanche Characteristics
Character/Avalanche Problem:
Deep Persistent Slab

Layer/Depth:
120-150 cm

Likelihood of Triggering
Sensitivity:


Spatial Distribution:
Widespread
Terrain
  Problem 2 Comments: Triggering one of these slides seems very unlikely. The mid-pack slab is very thick and strong. You'd have to find a very steep slope and shallow trigger point. I'd un-shade low elevation souths on the rose if I could. The FC here have already seen a couple waves of melt water and knife hard crusts guard the FC at the ground. I didn't observe upper elevations.
 Comments: I observed 5-10 mm SH on most aspects.
STABILITY TESTS
 Stability Test Results: 7700' south: ECTP29 dwn 75cm above (2/2) MFcr. Low shear quality that felt resistant as I dug. I don't expect this to be much of an issue in this terrain or on the more northerly slope that I dug.
SNOW STABILITY
 Snow Stability Rating for your observed area: Good Confidence: HIGH Trend: Improving
 Comments (aspects and elevations of instability, etc): Quickly moving to very good stability in the terrain I traveled. Pit on 7700' south added confidence in removing shading to the DPS problem rose.
BOTTOM LINE
 Comments: I'd assume much of the mid-storm activity was erased by additional snowfall. I only saw a couple crowns large enough to still be visible after the fact. One notable one was of course the D3 on Smoky Dome. There was lots of recent rider traffic in avalanche terrain in this zone with no results. The 2/2 and recent wind slabs didn't feel concerning and the deep persistent slab problem is well guarded by a fat, strong mid-pack. We're trending toward LOW in this zone without additional snowfall.
FILE ATTACHMENTS

190218_ElkRidge_00.jpg
Philips Creek/Soldier Creek wind slabs.

190218_ElkRidge_04.jpg
Philips Creek/Soldier Creek wind slabs.

190218_ElkRidge_37.jpg
False Summit sluff or cornice triggered slab.

190218_ElkRidge_42.jpg
Smoky Dome long view (left side of image).

190218_SmokyDome_Frost_03.jpg
Smoky Dome deep slab. Photo: Frost

190218_SmokyDome_Frost_01.jpg
Smoky Dome crown close up. Photo: Frost