Observation: NWAC Observer
Basic Information
Observation Details
Observation Date:
March 17, 2022Submitted:
March 17, 2022Observer:
NWAC Observer - Robin PenderyZone or Region:
West SouthLocation:
Silver Basin (NW-NE NTL)Signs of Unstable Snow
Recent Avalanches?
YesCracking?
None ExperiencedCollapsing?
None ExperiencedMedia/Attachments
Advanced Information
Weather Summary
Cloud Cover:
OvercastWind:
Light , SWNew/Recent Snowfall:
HN24 - 0
With high clouds and good visibility, it was a great day to go for a walk and track down some of the avalanches that were reported in the Crystal backcountry yesterday. We traveled outside of the ski resort between 5,000 and 6,500 ft on primarily N aspects.
The day remained overcast untill we left the field at noon. We found a brisk light wind, which kept temps feeling cool. There was some limited wind transport occuring with this breeze.
Avalanche Observations
| # | Date | Location | Size | Type | Bed Sfc | Depth | Trigger | Photos | Details |
|---|---|---|---|---|---|---|---|---|---|
| 1 |
Mar 16, 2022 () |
Three Way Peak N 6500ft |
D2 R3 |
SS-Soft Slab | O-Old Snow | 1.5ft |
AF-Foot r-Remote |
|
Report |
In addition to this remote triggered avalanche, there was one small (D1) avalanche visible near the crest of the ridge on Joe's shoulder (6250 ft, NW). This avalanche appeared to be skier triggered, and likely failed on facets above or weak grains within the early march crust.
We also saw very small wet loose natural avalanches on solar slopes from 3/16.
Snowpack Observations
At the top of FFF (6,000 ft), we found about 40 cms of snow above the early march crust. This snow is generally very light (F-F+ hardness), with a thin sun crust down about 30 cms. Between this sun crust and the mid march crust, we found evidence of weak grain types that we have been tracking (FCxr l.t 1 mm)
Snowpack tests gave us a mixed bag of information. Shovel shear tests failed very easily and highlighted facets just above the March crust as being our primarly layer of concern (STV down 39). Despite these results, we got no results on an extended column test, and so-so results from a propegation saw test (PST 60/100 END down 39).
All tests aside, the best evidence of instability was the large avalanche that occured yesterday immediatly in the area. While the weak layers within the snowpack may slowly be gaining strength, we chose to give them more time to heal, and skied low angle treed terrain.
Avalanche Problems
| Problem | Location | Distribution | Sensitivity | Size | Comments |
|---|---|---|---|---|---|
Persistent Slab
|
|
Unknown |
Layer Depth/Date: 3/8 Down 40-60 cms Weak Layer(s): Mar 8, 2022 (FC) |