Pro Field Report
Basic Information
Observation Details
Observation Date:
December 18, 2019Submitted:
December 19, 2019Observer:
SAC - Martin StefanZone or Region:
Galena Summit and Eastern MtnsLocation:
Prairie PeakSigns of Unstable Snow
Recent Avalanches?
None ObservedCracking?
IsolatedCollapsing?
IsolatedSnow Stability
Stability Rating:
FairConfidence in Rating:
HighStability Trend:
ImprovingBottom Line
Open, wind sheltered such as meadows hold persistent weak layers even on south-facing terrain.
Media/Attachments
Advanced Information
Weather Summary
Cloud Cover:
Mostly CloudyWind:
CalmSnowpack Observations
I found pockets of surface hoar in SSE facing meadows as low as 7600ft and E facing at 7300ft. Test results on 12/7 are improving in some pits, still reactive in others. I could not see any clear pattern as to where 12/7 is gaining strength, and will treat it as weak until proven otherwise.
Interestingly, I also found facets on the melt-freeze pack of old snow on the ground at high elevations, probably in a pocket where wind had deposited before 11/26.
Pit 1: 7600ft SSE HS 55cm
12/7 @ 22cm from gnd faceting SH on 4cm MFcr, gave ECTN 12 PST 20/100 (end)
12/11 @ 40cm FC on 2cm MFcr, no results, not much of a slab on top of it
This meadow was completely open to E through S. It looks like the sun was still not powerful enough to kill the 12/7 SH before it got buried.
Pit 2: 8300ft E HS 65cm
12/7 @ 20cm SH on 1cm MFcr, SH looked to be fairly well preserved with more or less upright 3mm crystals, but gave no results on ECT or PST.
12/11 @ 45cm FC on MFcr 0.5cm
Pit 3: 8800ft ESE exposed to a bit of wind (see Media)
11/26 @20cm from gnd, 3cm layer of 1-2mm FC on refrozen concrete, ECTP26 PST 20/100 (End)
12/7 @45cm, SH, no result on ECT, PST 65/100 (End)
12/11 @60cm, a clear interface and possibly small FC, SH killed by wind?
Avalanche Problems
| Problem | Location | Distribution | Sensitivity | Size | Comments |
|---|---|---|---|---|---|
Persistent Slab
|
|
Layer Depth/Date: 12/7 Comments: Sensitivity has started to vary with some more stable results in places |
Terrain Use
I avoided avalanche terrain where 12/7 was present.