Observation: NWAC Forecaster

All Observations

Basic Information

Observation Details

Observation Date:
December 5, 2022
Submitted:
December 5, 2022
Observer:
NWAC Forecaster - Josh Hirshberg
Zone or Region:
East North
Location:
Goat Peak (S-W-NW. 2200-5800ft)

Signs of Unstable Snow

Recent Avalanches? 
None Observed
Cracking? 
Isolated
Collapsing? 
None Experienced

Media/Attachments

Large surface hoar covered almost every snow surface. Goat peak, 4,700ft
Large surface hoar covered almost every snow surface. Goat peak, 5,700ft
Very large surface hoar covered most snow surfaces. Many were 10mm (1cm)
This profile site often receives wind loading. Older wind-drifted slabs rested on the mid-November facets. Goat pk, 5768ft
A propagation saw test indicates that propagation is likely on the mid-November facets. PST 20/100 END on FC (2.0mm). Goat Peak, 5768ft
Easy snowpack test results show the potential for triggering avalanches where older drifted slabs rest on the mid-November facets. ECTP 2 @ 29cm on FC (2.0mm). Goat Peak, 5768ft
Large 2mm facets (mid-Nov) in the lower half of the snowpack remain very angular and sharp in the eastern mountains. Goat Peak, 5768ft.
Silverstar Mtn with Driveway Butte in the foreground.
Shallow but consistent snow cover in the eastern foothills south of Winthrop.

Advanced Information

Weather Summary

Cloud Cover:
Clear
Wind:
Calm

Another clear, calm day with temperature inversions.

Snowpack Observations

Very large (10mm) surface hoar covered every surface. The sun was slightly warming steep south slopes, just enough to make trees drop snow from their branches.

Below 5,000ft we found a mostly shallow and weak snowpack with most layers softer than 4 Finger hardness.
At 3800ft, E aspect we found an almost entirely facetted snowpack of 50cm with larger, more developed facets in the lower snowpack and a thin, stout crust on the ground.
At 4,700ft, S aspect, HS 55cm. We found a single 8cm thick crust in the middle of the snowpack from all of the late-Nov rain and warming events. It separated facetting recent snow in the upper snowpack from the large mid-November facets in the lower snowpack.

Profile-
5768ft, flat, north ridge of Goat Peak. Targetted a location that had received previous wind loading
HS 56cm
56-55cm- F- hard, SH (10mm)
55-48cm- F hard, FCsf (0.3mm)
48-35cm- 4F hard
35-29cm- 4F hard, RGfc (0.3-0.5mm), older wind drifted snow
29-8cm- F+ hard, FC (1.5-2.0mm), some very subtle melt forms @ 29cm, mid-Nov FC; Tests- ECTP 2 @ 29cm, PST 20/100 END @ 29cm
8-0cm- 4F+ hard, MF(FC) (1.0mm)