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PROFESSIONAL OBSERVATION FORM
 Start Date: 04.12.17 Name: Savage Operation: SAC
 Drainage/Route:  Silver Ck/Boulder Ck (ridge going S from Silver Peak) Observed Terrain:  6700-9900', E-S-W Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: 2-6cm HST: 2-6cm Sky: SCT Precip: Temps:
 Ridgeline Wind: Moderate and Gusty from the SW
 Blowing Snow: Prev Snow Available for Transport: Small amounts
 Comments: Skiff new snow in Baker Ck parking lot @1200hrs: 2cm @8300': 5-6cm @9300' and up. Sun-affected slopes will not have much snow available for transport after today.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 20+ Smoky and Boulder Mts Today 1 WL N SE alpine Lots of very small WL late this morning and this afternoon on E-SE-S. SW and W were getting direct sun when I left. Mostly tiny dribbles but saw a handful of legitimate D1 slides.
 Comments: Photo is one of the larger ones I saw today glassing everthing I could from exposed ridgeline.
SNOWPACK OBSERVATIONS
 HS: Not observed 
 Upper Pack: >9000': dry PP on NW-N-NE, moist PP becoming wet on E-S-W...hard crusts beneath new snow in wind exposed areas with some tiny FC at crust/new snow interface, 10-20cm DF from last storm in shady sheltered areas
8000-9000': 2-4cm new snow on 10-15cm DF from last storm with some breakable crusts...all of the 4-11 storm snow and previous storm snow was moist-damp-wet on W-S-E slopes and surface was moist on W/NW and E/NE...true S was close to corn but unsupportable beneath new snow in many places
<8000': spring corn, mostly supportable 
 Middle Pack: Not observed 
 Lower Pack: Not observed 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Loose Wet

Layer/Depth:
5-10cm

Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Specific
Terrain
  Primary Concern Comments: Sheltered, rocky alpine cirques. Lots of small naturals today.
 
Avalanche Characteristics
Character/Avalanche Problem:
Wind Slab

Layer/Depth:
10-20cm

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Isolated
Terrain
  Problem 2 Comments: Not that many fresh wind slabs formed up here last night. Lots of wind affect and some cornice growth, but less wind slab than expected/forecast. Older slabs from last storm becoming unreactive where I could test them, but still have some uncertainty there. Did not get on northerly slopes.
 Comments: Although they were small, there was more WL activity than expected and it probably should have been the primary problem today. The fresh wind slab problem barely materialized in this area.
STABILITY TESTS
 Stability Test Results: No standard tests performed. Tugging on hand columns showed "slippery" moist interface between new snow and crusts on some sun-affected slopes. Ski cutting test slopes with small wind slabs produced no cracking or results.
SNOW STABILITY
 Snow Stability Rating for your observed area: Good Confidence: HIGH Trend:
 Comments (aspects and elevations of instability, etc): Hazard confined to alpine terrain: needed to pay attention a bit in wind-loaded areas, especially below new cornice growth, and in/below sunny+rocky+wind-sheltered terrain.
BOTTOM LINE
 Comments: Transition day with the upper 20cm getting moist to wet on W-S-E aspects above 9000'. Before today, upper elevation slopes had much more of a winter flavor - now, they are a "more typical for April" mixed bag based on aspect and exposure. 8000-9000' zone had better stability but poorer traveling conditions (breakable crusts and slop). Could be some unforgiving riding and skiing conditions on cloudy days until today's surface gets buried.
FILE ATTACHMENTS

170412BouldersWLresized.jpg