Observation: NWAC Forecaster

All Observations

Basic Information

Observation Details

Observation Date:
March 21, 2023
Submitted:
March 21, 2023
Observer:
NWAC Forecaster - Katie Warren
Zone or Region:
East South
Location:
Ahtanum Meadows (3200 to 6800ft; All aspects except due N)

Signs of Unstable Snow

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

Media/Attachments

Snow profile in sheltered terrain near 6400ft. The upper pack is capped by a melt-freeze crust with dry, strengthening, settled storm snow below. The interface with the Valentine's crust showed no reactivity in stability tests.
The melt-freeze crust existed to the ridgeline, but poor visibility prevented access to north facing terrain.
Light snow with poor visibility near the ridge made for challenging travel.
The cloud deck hovered around 5600ft.
At lower elevations, particularly on southern aspects, holes and other hazards are beginning to emerge from the snowpack. This photo is approximately 4500ft.

Advanced Information

Weather Summary

Cloud Cover:
Obscured
Wind:
Calm
New/Recent Snowfall:
Just a dusting of new snow below 6400ft and around 2cm above.

I was surprised by the low cloud deck and extremely poor visibility today. Some light mixed precipitation at the trailhead quickly changed over to snow by 4000ft. Winds were calm even in exposed along the ridge at 6800ft.

Snowpack Observations

The snowpack is just showing signs of the spring thaw at lower elevations, with some nearly bare patches of road. Steep south-facing aspects had bare spots up to 4800ft. The pack consists of well-settled snow at these lower elevations.

At upper elevations, a 2cm melt-freeze crust caps the snow surface on all aspects where I traveled. Low visibility prevented me from getting info from true northerly terrain. Most locations have a dusting of new snow over this crust, up to 2cm deep in some places. I dug a snow profile at 6400ft in flat sheltered terrain. The height of snow ranged from 230-250cm in this area. Below the surface crust is around 60cm of settled storm snow above the Valentine's Crust, and the MLK crust is down about 90cm. Snow above and below these crusts is P hard and showed a favorable bond to both crusts. Stability tests produced no results on these deeper layers. I did observe a storm interface down 20cm, and while it was a clean, planar shear, it took strong force before it failed.

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