Observation: NWAC Forecaster

All Observations

Basic Information

Observation Details

Observation Date:
November 29, 2022
Submitted:
November 29, 2022
Observer:
NWAC Forecaster - Josh Hirshberg
Zone or Region:
Stevens Pass
Location:
Stevens Pass Resort (4,000-5,200ft NW-NE, S-SE)

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
None Experienced
Collapsing? 
None Experienced

Media/Attachments

Mid-November facets (1.5mm) found near SPMR. NE, 5050ft
Mid-November facets (1.5mm) found near SPMR. NE, 5050ft
A quick profile adjacent to the ski area to identify the mid-November facets (@ the blue card) near the ground. This slope had seen significant wind loading. HS 183cm. NE, 5050ft
https://youtu.be/pGg3jXEE6us

Advanced Information

Weather Summary

Cloud Cover:
Overcast
Wind:
Light , E
New/Recent Snowfall:
HN24 5cm- accumulated while we were touring

Very cold. S-1. No blowing snow, tho plenty is available

Typical Gemini saddle cornice/wind slab location may have slid on Sunday, D1. ENE, 5,000ft

Snowpack Observations

30-40cm of low-density HST from 27-28th
Height of snow varied considerably w elevation/location:
4700ft, N- 70-80cm
4800ft E- 115cm
Drifts over 180cm

Probing at numerous "non-polar" locations yielded progressive hardness w 2 crusts in the lower 1/2 of the snowpack and firm mid-Nov melt forms near the ground.

Found the Mid-Nov (11/22) facets on a small, steep, shaded, wind-loaded feature adjacent to the upper Gemini run. They were dry, intact, w minimal rounding. See photo/video.
NE, 5050ft, HS 183cm
42-37cm: 1F, MF(FCxr), friable crust from rain on facets on Nov 22
37-0cm: 4F-, FC, 1-1.5mm, formed during mid-Nov high pressure
Attempted a DT test, though slope didn't produce reliable results.

Avalanche Problems

Small Loose Dry were easy to trigger on 40 deg slopes, though not fast-running. Wind slab problem seemed very localized. Didn't get to assess this as well.

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