Pro Field Report
Basic Information
Observation Details
Observation Date:
January 8, 2021Submitted:
January 8, 2021Observer:
SAC - Lundy, Davis, DalyZone or Region:
Soldier and Wood River Valley MtnsLocation:
Baldy OB/Bassett Gulch (8400-8900, W-N (variety of aspects/elevations in bounds))Signs of Unstable Snow
Recent Avalanches?
None ObservedCracking?
IsolatedCollapsing?
IsolatedSnow Stability
Stability Rating:
GoodConfidence in Rating:
ModerateStability Trend:
ImprovingBottom Line
Snowpack in the Baldy OB is thin and very weak. Outside of wind-affected areas, the slab seems too thin and soft to cause widespread instability. It doesn't take much effect from the wind to provide a stiff enough slab to produce collapsing/cracking and poor snowpack test scores.
Advanced Information
Weather Summary
Cloud Cover:
OvercastWind:
LightNew/Recent Snowfall:
A few cm'sTop of Baldy was in and out of the clouds.
Avalanche Observations
| # | Date | Location | Size | Type | Bed Sfc | Depth | Trigger | Photos | Details |
|---|---|---|---|---|---|---|---|---|---|
| 1 |
Jan 5, 2021 (+/- 1 day) |
Bassett Gulch N 7700ft |
D2 | SS-Soft Slab | O-Old Snow | N-Natural |
|
Report |
Snowpack Observations
Snowpack is very thin and weak and there is only reasonable coverage on mid to upper elevation shaded slopes. December weak layer presents as well developed depth hoar in places and is uniformly F- in hardness. 11/17 dirty crust is almost completely eaten away, and solstice crust is also quite deteriorated. On middle and upper elevation shaded aspects, the slab is 25-30cm thick and F to F+ in hardness - generally insufficient to produce instability. But it takes very little wind-stiffening to change the equation.
Big North, 8500', N: HS 60cm. 12/11 FC/DH down 30cm - ECTX, PST25/100end. Slab was barely F+ over F- weak layer. We had a collapse near the pit site where the slab was slightly wind-stiffened.
Top of Bassett, 8900', WNW: HS 50cm. Slab was just slightly stiffer from wind (4F-) but still 30cm thick - this was enough to produce ECTP14, PST29/100end.
Avalanche Problems
| Problem | Location | Distribution | Sensitivity | Size | Comments |
|---|---|---|---|---|---|
Persistent Slab
|
|
Layer Depth/Date: 30cm Weak Layer(s): Dec 11, 2020 (FCsf) Comments: Problem is more reactive where there is wind-stiffening of the slab. |
Terrain Use
We avoided consequential avalanche terrain.