Pro Field Report
Basic Information
Observation Details
Observation Date:
March 18, 2022Submitted:
March 18, 2022Observer:
SAC - Chris LundyZone or Region:
Banner SummitLocation:
Cape Horn Ridge (6700-8800', SE-E-NE)Signs of Unstable Snow
Recent Avalanches?
None ObservedCracking?
None ExperiencedCollapsing?
None ExperiencedSnow Stability
Stability Rating:
FairConfidence in Rating:
ModerateStability Trend:
SteadyBottom Line
The persistent slab problem seems less pronounced than what I observed in the northern Sawtooths yesterday, primarily due to a thinner slab from less snowfall since March 8th. I found the weak layer (facets on a crust, or just facets) on shady, mid to upper elevation slopes. It was buried beneath a 14" thick slab that produced poor test results.
Media/Attachments
Advanced Information
Weather Summary
Cloud Cover:
Mostly CloudyWind:
Light , SWNew/Recent Snowfall:
Trace of new overnightMorning was close to overcast, but transitioned to broken by afternoon with a mix of sun and clouds. Temps were warm, but the clouds and breeze kept things cooler than it felt yesterday. Winds were light but gusty, there were brief spells when it was blowing moderate and moving small amounts of snow.
Snowpack Observations
Main objective was looking at weak layers in the top portion of the snowpack, particularly the 3/8 crust/facet layer.
@7800', E-NE: 25cm of snow on 3/8 - no real slab
@8200', NE: 3/8 rain crust 33cm down. ECTN's or ECTX's, but clean hand shears.
@8400', NE: No rain crust, but obvious, well-developed 2cm thick FC layer down 35cm at the 3/8 interface. ECTP13, ECTN (x3). 1/20 down 50cm, F+ FC, ECTX. This was a "shady" NE in some trees, compared to the sunnier NE in the next pit.
@8800', NE: HS 240cm. 3/8 MFcr/FC down 35cm. I'm fairly certain this crust formed during the warm spell after the rain event - it didn't rain this high in the Banner zone. Bottom of slab was 4F+. ECTP8,13,15 (see video). 1/20 down about 55cm, F+ FC, ECTX.
TL;DR: Persistent slab problem seems more pronounced where a crust exists at the 3/8 interface. Seems there is just barely enough of a slab.
Avalanche Problems
| Problem | Location | Distribution | Sensitivity | Size | Comments |
|---|---|---|---|---|---|
Persistent Slab
|
|
Layer Depth/Date: 35cm Weak Layer(s): Mar 8, 2022 (FC) Comments: Rose is forecasted location |
|||
Wet Loose
|
|
Layer Depth/Date: 10-20cm Comments: I did not gather much info on this problem, but pushing on one small mid elevation slope, the snow seemed like it wanted to peel off the 3/8 crust |
Terrain Use
I avoided slopes 35* and over