Observation: NWAC Forecaster

All Observations

Basic Information

Observation Details

Observation Date:
January 29, 2023
Submitted:
January 29, 2023
Observer:
NWAC Forecaster - Josh Hirshberg
Zone or Region:
Stevens Pass
Location:
Lanham Creek (N-E, 3,000-6,040ft)

Signs of Unstable Snow

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

Media/Attachments

the northwest face of Jim Hill.
Glacier Peak with Minataur Peak in the foreground.
Surface hoar on a ridge. Lanham Creek, 5,500ft
Needle-like rime covered trees at the ridge-top. Lanham Creek, 5,500ft
The west faces of Deadhorse (L) and Big Chiwaukum Peaks (R).
Wind features from both east and west in the past 2 weeks. Wind drifted snow was not reactive to the weight of a skier. Lanham creek, 5,500ft.
Very slick, icy surfaces had us wishing for crampons and ice axes at low elevations. Lanham Creek, 3,000ft
https://youtu.be/RuODMw7GpzU

Advanced Information

Weather Summary

Cloud Cover:
Clear
Temperature:
18°F
Wind:
Calm , E

Frigid temperatures. Infrequent light gusts of E wind, no wind transport in any areas observed.

Avalanche Observations

 #  Date Location Size Type Bed Sfc Depth Trigger Photos Details
3 Jan 13, 2023
() 		Big Chief Mtn- East Highlands Bowl
E 5600ft 		D2 WS-Wet Slab O-Old Snow 2ft N-Natural
Old crowns, likely from the MLK storm Jan 12-13th. While unconfirmed, these avalanches may have run on the 1/4 surface hoar.
An old crown (1/12?), a fresh, shallow slab avalanche, and recent roller balls. East Highlands Bowl, NE-SE, 5,800ft
Report
Big Chief Mtn- East Highlands Bowl

Saw a few older slab avalanches that may have run on the Jan 4th surface hoar during the MLK storm.

Snowpack Observations

Very cold temperatures kept us moving all day and limited in-depth snowpack observations.

We found evidence of older wind effects and features from the past week. All wind-affected snow was unreactive. Extensive slope testing found only minimal sluffing on the steepst slopes (>45 degrees). Found plenty of frozen rollerballs and "chunder" from the Jan 25-26th warm-up.

Found near surface facets on most surfaces above 3,400ft. Surface hoar was observed in specific to isolated terrain including valley meadows and at ridge tops.

Below 3,400ft and under tree canopy, surfaces are a Knife hard ice crust which includes all precip since the MLK storm. Above this elevation, surfaces under canopy are softer though minimal previously dry snow remains above the MLK crust.
In open areas above 4,000ft, the MLK crust varied in depth from 17-26cm with elevation and aspect. I consistently found a thin layer of 4 Finger hard, rounding facets (0.5mm) immediately above the MLK crust. At 5,4000ft, E, the MLK crust was a matrix of 2 crusts with a thin weak layer sandwiched between them.

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