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PROFESSIONAL OBSERVATION FORM
 Start Date: 04.03.19 Name: Davis Operation: SAC
 Drainage/Route:  Silver Peak Ridge Observed Terrain:  6600-9900', All Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: 2-12 cm HST: 2-12 cm Sky: VAR Precip: Temps:
 Ridgeline Wind: Light and Intermittent from the NW
 Blowing Snow: None Snow Available for Transport: None
 Comments: Today's weather had it all thanks to some deeper convection. Low clouds hung at middle elevations and breaks in the overcast provided short 5-10 min bursts of intense sun. On the way out (1300ish) a fierce squall pelted down sleet at 7500 and rain at 6700 (Baker parking). A quick hitting rain shower also soaked Ketchum while it was dry at the hospital.
AVALANCHE OBSERVATIONS
 No. Location Date Size Type Trigger Aspect Elevation Comments
 Several Lightning Point Today 1.5 WL N SE 10,200 I watched/listened to more than a dozen smallish WL initiate on Lightning before noon. They occurred within minutes of a sun break hitting the rocks, picking off the low-hanging fruit. A solid hour of sun would have been enough to make this more widespread.
SNOWPACK OBSERVATIONS
 HS:  
 Upper Pack: -HST 1" at Baker, 4" @ 8200', 5" @ 9900'
-The primary rain line was ~6,800' although the new snow was moist to 9900'
-A 2mm rain crust coated the surface of the new snow between about 7000 and 9900', lightly faceted in some areas.
-The main crust below the HST was soft and weakly frozen in most areas below 8500' 
 Middle Pack:  
 Lower Pack:  
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Wet Loose

Layer/Depth:
12 cm

Likelihood of Triggering
Sensitivity:
Touchy

Spatial Distribution:
Specific
Terrain
  Primary Concern Comments: I triggered some pretty large galloping roller balls and small moist/wet sluffs on the way out.
 Comments: I saw no signs that the HST had formed any new wind slab issues.
STABILITY TESTS
 Stability Test Results:
SNOW STABILITY
 Snow Stability Rating for your observed area: Poor Confidence: HIGH Trend: Worsening
 Comments (aspects and elevations of instability, etc): Generally LOW for the time I was present considering the predictable and small nature of the slides I saw. I would expect the danger to easily reach MOD later this afternoon. It would have only taken an hour of sun to see more widespread WL activity.
BOTTOM LINE
 Comments: I witnessed wet loose in favored, very steep, rocky terrain but the sun wasn't out quite long enough to really get things going in adjacent terrain. The rain crust is widespread in this area and may be something to watch if the sun/warmth doesn't hit it too hard before the next storm.
FILE ATTACHMENTS

190403_Silver_02.jpg
2mm rain crust that coats all aspects from about 7,000 to at least 9900'.

190403_Silver_04.jpg
Most of these occurred in a series of short 5-10 min sun breaks. Prolonged sun would have made this problem more widespread.