Pro Field Report
Basic Information
Observation Details
Observation Date:
March 26, 2023Submitted:
March 26, 2023Observer:
SAC - Jon PreussZone or Region:
Galena Summit and Eastern MtnsLocation:
Galena Peak (NW-S-W; 7,300-10,200')Signs of Unstable Snow
Recent Avalanches?
None ObservedCracking?
IsolatedCollapsing?
IsolatedBottom Line
A slab is growing over several different crust layers in the upper two feet of the snowpack on slopes facing the sun. Sensitivity increases with elevation and slopes with recent wind-drifted snow.
Advanced Information
Weather Summary
Cloud Cover:
ObscuredWind:
Light , SNew/Recent Snowfall:
HN during the day: ~3cmLight, steady snow showers fell during the day. Accumulations were around an inch from 1000-1530 hr. Winds were light and variable. I didn't observe any snow blowing around, but all aspects have a small amount of snow available to transport.
Avalanche Observations
No new avalanches observed.
Snowpack Observations
I focused digging on south facing slopes to see the distribution and slab character sitting atop recently formed melt-freeze crusts. As I gained elevation from my first pit at 9,000' to 9,700', the new snow grew in thickness from 6 to 20cm and was slightly denser from wind-affect. The fresh snow has an interface of near-surface facets sitting on a crust.
Three different crust layers make up the upper two feet of the snowpack. The second crust had mixed results of ECTN8, 9 and ECTP9 down 28 cm. The third crust down had similarly mixed results of ECTN18, 21 and ECTP21 down 48 cm. The slab is on the brink of becoming thick enough for avalanches. The slab may already be ripe enough for triggering avalanches in areas with more wind-loading and higher storm totals than in this location.
Avalanche Problems
| Problem | Location | Distribution | Sensitivity | Size | Comments |
|---|---|---|---|---|---|
Persistent Slab
|
|
Layer Depth/Date: 28-48 cm Comments: *reflects areas where I observed the snowpack. |
|||
Wind Slab
|
|
Layer Depth/Date: 30cm Comments: I stomped around on a number of wind pillows with only little reaction. They were mostly soft slabs with some older generation of denser slabs. They seemed to be dead, but I was able to get some cracking and one collapse. I imagine you could kick off some slabs sitting on top of faceted snow. |
I only focused on southerly slopes in my observations, so I'm not including the known persistent slab problem deeper in the snowpack on the northerly side of the compass.
Terrain Use
Solo travel. Besides walking up the approach in historical runouts, I stayed out of avalanche terrain. One of which already released during the last big avalanche cycle.