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PROFESSIONAL OBSERVATION FORM
 Start Date: 02.01.19 Name: Lundy Operation: SAC
 Drainage/Route:  South of McDonald Peak Observed Terrain:  7400-9800', SE-E-NE Zone/Region:  Sawtooth Mountains
WEATHER OBSERVATIONS
 HN24: HST: Sky: BKN Precip: Temps:
 Ridgeline Wind: Moderate from the SW
 Blowing Snow: None Snow Available for Transport: None
 Comments: Increasing clouds this morning, quickly becoming BKN by late morning. Warm temps but cloud cover kept solar crusts from thawing.
AVALANCHE OBSERVATIONS
None Reported
SNOWPACK OBSERVATIONS
 HS: 120-160cm at mid to upper elevations 
 Upper Pack: Variable surfaces...1-3cm MFcr on solars. FCsf on E though N at low to mid elevations. Widespread wind affected snow at upper elevations has prevented extensive surface faceting. 
 Middle Pack: Lower elevations lack any slab structure, but middle and upper elevations have a stout slab. Pits on SE and NE at upper elev both had a P hard slab 
 Lower Pack: 20-40cm of FC and/or DH. MId/Upper elevations: on solars the top of the FC was dry and 4F, but became 1F and moist near ground. On shady, the FC/DH was dry and 4F+. Deep slab structure seems to have changed little during the high pressure. 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Deep Persistent Slab

Layer/Depth:
11/22 & 12/11, 90-130cm

Likelihood of Triggering
Sensitivity:
Unreactive

Spatial Distribution:
Widespread
Terrain
  Primary Concern Comments: 
STABILITY TESTS
 Stability Test Results: 9400', NE: HS 160cm, 130cm P hard slab over 4F+ FC/DH, Cross slope PST 55/135end
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
BOTTOM LINE
 Comments: Was a bit surprised to see so little change in the deep slab structure. Hardness, moisture, and test results have shown little change from the week of high pressure and warm temps. I still think it'll take a big load to reactivate the deeper layer, but I'm not ready to write it off just yet.
FILE ATTACHMENTS

190201_nsf_sh.jpg
FCsf and SH on mid elevation E aspect

190201_nsf.jpg
FCsf on mid elevation E aspect