High presence of glide cracks evident along Seattle Ridge and along the Library
Observation: Turnagain
Location: Center Ridge
Toured up from Center Ridge parking lot around 10am, walked to the weather station and over to the north side of center ridge facing the library. Goals for the day were to dig pits on the north side of center ridge and investigate surface conditions.
Observer Comments
Weather
10am at Center Ridge PL ~1000'
Calm winds, clear skies, -10°C air temp
12pm at pit locations ~1900'
Calm winds, few clouds, -4°C air temp
3pm at Center Ridge PL ~1000'
Calm winds, clear skies, -5°C air temp
Very strong inversion!
Snow surface
Observed a wide range of surface hoar that varied with elevation
1-2cm sized surface hoar from 1000' to 1370' (pic below)
2mm surface hoar mixed with near-surface facets from 1370' to 1830'
At pit location @ 1960' just observed near-surface facets (1mm) mixed with decomposing stellars
No wind effect below treeline, wind affected rollovers near treeline showed stubborn surface wind slabs
Great snow in the trees, loud pow!
Snowpack
We dug a series of three total pits on a N aspect at ~1900' on Center Ridge
Height of snow ranged from 210cm to 135cm between pits
Key stability test results:
In pit with 135cm depth, PST 58/100 END x2 94cm down on a layer of facets where the thanksgiving crust was
ECTX in all pits
In pit with 210cm depth, CT25 SC 30cm down on a hardness interface, result did not repeat in second CT
Rounding basal facets at base of snowpack
Overall we found fair structure and good stability in this location
Surface Hoar at 1400'
Surface gains at 1800'
Surface Hoar at 1000'