Observation: Turnagain

Location: Magnum

Route & General Observations

Toured up Magnum to monitor the basal facets at the 3,000′ elevation band.

Overcast with valley fog. Warm, 30F. East wind light to moderate below
ridgelines with stronger gusts on ridgelines. Light snowfall adding a trace to
1cm through day.

Red Flags:
Wind loading
Cracking (small and localized)

Wind slab. Winds were visibly loading slopes just off upper elevation ridges on
west, south and north aspects.

Full pit profile:
Dug at 3,000′, SSW aspect, 26 deg (see image below).
No interesting or red flag results. The top meter of the pack has bonded well in
this location where wind and warm storms have laid down various layers of dense
snow, wind packed snow and one weak rain crust ~60cm down. The current sensitive
wind slab seen near ridgelines was not present.

Deep Slab monitoring:
The real purpose of digging was to see how the October and November facets
are looking in a start zone/bed surface elevation on Turnagain Pass (~3,000′) that was
neither wind loaded nor thin. We have dug a lot in thin areas (likely trigger points)
to look at the facets but not much where 2m of snow is compressing them. Sure enough,
the facets have gained significantly in hardness and strength in this location. Hardness
has gone up (great sign – from fist to 1 finger) and they are not falling out of the pit
as when they lacked cohesion a month ago but are now bonding with their neighbors. The Nov
facet layer has thinned (hard to judge but ~5cm) while the Oct layer seems to have thinned
a couple cm’s. This supports the observed harness and rounding/bonding increase.

The December 1st dust layer is visible which provides a great marker for the top of the
November facets.

Take home – the deep slab problem is getting better by the day. It has also healed
and not looking to be an issue at elevations below 2,000′. Fitz talks about this
in an observation from 2/3.

Photos & Video
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