Observation: Turnagain

Field Observations
Jan.1, 2015

Route
Sunburst parkinglot to SW side Magnum (3400′) PMS bowl

Weather
Temps: high 20’s F
Wind: moderate w/ gusts in 20’s mph NW
Skies: broken
Precip: none

Obvious Signs Of Instability
Recent Avalanches-NO
Shooting Cracks-NO
Collapsing – NO

Surface Obs
1000′ – 1” crust on 4″ of old snow
1600′ – Rain crust disapears
1600 – 2000′ – 4-6″ new snow. Some terrain features are scoured w/ pockets of loose dry snow.
2000 – 3400′ – Variable surface conditions. Very scoured on many terrain features with pockets of wind
deposited snow. (6″ -12″) Along southern aspect of Magnum ridge there was 4-6′ wind deposited snow.
*In general as we gained altitude there were larger areas of scoured slopes and ridges. Scoured surfaces
were greater near ridges and on Western aspects of Magnum.

Snow Below the Surface:
We found the buried surface hoar (BSH) layer from Dec. 14-17th still in tact. We had full propagation in our
isolated test pits. The BSH layer seemed to be more reactive, meaning it took less force to propagate, with
the addition of the wind-loaded snow. See results below. Windslabs varied from 8″ – 12″ and appeared to
be less reactive with little to no propagation potential – failed with a lot of force at a hardness change from pencil to 1finger.

2 Pits at 3280′ – Aspect: SW, HS: 180cm & 110cm, Windslab varied from 15cm – 25cm, Buried surface hoar
(BSH) layer was between 45cm – 55cm from surface.
Results: ECTP14 SC, ETCP21 SC at BSH layer 55cm from surface, ECTP17 SC, ECTP17 SC at BSH layer 45cm
from surface
ECTP17 RP at harness change 15cm from surface(wind slab) ECTN11 at hardness change 15 cm from
surface