Pro Field Report
Basic Information
Observation Details
Observation Date:
January 3, 2020Submitted:
January 3, 2020Observer:
SAC - Martin StefanZone or Region:
Soldier and Wood River Valley MtnsLocation:
Warm Springs DrainageSigns of Unstable Snow
Recent Avalanches?
None ObservedCracking?
IsolatedCollapsing?
WidespreadSnow Stability
Stability Rating:
FairConfidence in Rating:
ModerateStability Trend:
SteadyBottom Line
On low elevation solars where the snow is thin the slab from this last storm rests on a weak, rotten base. On shadier aspects we have the usual weak layers from beginning of December still showing sings of instability.
Advanced Information
Weather Summary
Cloud Cover:
Mostly SunnyTemperature:
30sWind:
CalmA calm and balmy afternoon in the Wood river valley, some thin clouds veiled the sun around 3pm.
Snowpack Observations
On low elevation solars the 12/31 storm slab rests on a weak mess of faceted crusts and just facets, at least in areas with little to no sage brush. The storm slab was getting baked and moist in the afternoon sun, but the facets below were dry.
On higher and shadier slopes 12/7 is present, at 7600' on a wind loaded open SW slope I had HS 80cm with 30cm 4f wind slab on FCxr and 12/7 60cm down. No DH, moist small FC to gnd. The sun had not baked the storm slab noticeably here.
12/7 produced ECTP24sp and a snappy PST25/100end, no result on the old/new snow interface. After leaving the pit, not more than 3m away I collapsed the whole slope.
Avalanche Problems
| Problem | Location | Distribution | Sensitivity | Size | Comments |
|---|---|---|---|---|---|
Persistent Slab
|
|
Layer Depth/Date: 12/7 50-60cm Comments: 12/7 is present and still active in this area on everything but the sunniest slopes. |
On sunny aspects clear of sagebrush the base for the 12/31 storm is another PWL, but given how thin the total snowpack is in these areas it will be isolated to planar slopes that have little to no sagebrush.
Terrain Use
I avoided avalanche terrain