Pro Field Report
Basic Information
Observation Details
Observation Date:
March 4, 2023Submitted:
March 4, 2023Observer:
SAC - Preuss, Coba, MackayZone or Region:
Soldier and Wood River Valley MtnsLocation:
Morgan's Ridge (N-W-S; 6000-8400')Signs of Unstable Snow
Recent Avalanches?
None ObservedCracking?
None ExperiencedCollapsing?
IsolatedBottom Line
We found a poor structure on north-facing slopes with a foot-thick slab over weak, sugary facets. We experienced less collapsing than expected, given that structure. The upper snow in the middle and lower elevations is likely missing a larger slab that other areas have acquired with recent wind-loading or higher snow totals.
Media/Attachments
Advanced Information
Weather Summary
Cloud Cover:
OvercastWind:
Light , SNew/Recent Snowfall:
HN 3-6 cm; HST 28 cmSnow showers were intermittent throughout the day with no significant accumulation.
Snowpack Observations
We dug on a north-facing slope at 8300' and found a 1 foot slab (30 cm) over weak, sugary facets. A thin melt-freeze crust was bridging the newer snow above into a cohesive slab. Extended column tests produced propagating results with 12, 14, and 14 hits. A buried surface hoar layer was found, with its feathers lying down about 8 inches (20 cm) from the surface.
Much of the south-facing terrain has significant sage brush popping out of the snowpack. Some of the higher start zones have enough coverage but have firm crusts.
Avalanche Problems
| Problem | Location | Distribution | Sensitivity | Size | Comments |
|---|---|---|---|---|---|
Persistent Slab
|
|
Layer Depth/Date: 30cm Comments: The rose reflects the terrain we observed today. |
The persistent problem at the middle and lower elevations weren't causing as much collapsing as expected in this area. The slab likely needs more load from wind-loading or more new snow to become more of an issue in sheltered locations.
We didn't come across any fresh wind slabs in this area.
Terrain Use
The recent avalanche activity in this zone kept our open terrain conservative. We stuck to low-angle ridgelines and avoided dropping into bowl features with higher consequences.