Observation: NWAC Forecaster

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Weather Summary

Winds were shifting and variable, and generally increasing into the afternoon but this may have also just been the perception- as we gained elevation. Our skin track was sifted over to unrecognizable in many open exposed places when we skiied back down, however.

Snowpack Observations

As we started the tour, snow surfaces were moist and somewhat gloppy up to about 4,500ft, even on the northerly aspects.
The ridgeline was often obscured by snowfall and cloud, only lending itself to an occasional glimpse on the ascent.

A fair amount of wind transport was occurring above ~5,000ft, and the snow often felt slabby and kind of punchy with recently buried wind slab, and freshly forming ones. A thin, eggshell like crust from 2/13 was often 10-15cm beneath the surface, with notably weaker snow below it. This general structure was found from 4,000ft up to well over 6,000ft. This, along with patchy stiffer windslab to 1F or even P hardness in places only added to the punchyness. Up at 6,000ft I thought we might get a collapse or two due to some thicker windslabs, but never did.

Tilt tests, hand shears and compression tests failed easily just beneath the thin crust from 2/13 on 1mm faceted grains. The interface that was just buried (2/17) also tended to fracture in some places, but there was only a few centimeters on it.
Compression tests failed with hard force just above the MLK crust, but one test failed both above and beneath it. See profile pic.

Wind textures were present in the upper starting zone of the Swath, and we retraced our steps down the sheltered and less steep slopes for the descent.
Our skin track was all but erased by the wind in many open slopes lower down later in the day.