APU Snow Science 1 class field day at Turnagain.
Route: Sunburst uptrack & hop over to Magnum NW ridge uptrack.
Weather: Single digits temps at parking lot, but warmed up during the day with some sun through
mostly overcast sky. Calm to light winds. No precipitation.
Signs of instability: None observed – no recent avalanches, no whumphing/cracking/collapsing.
Surface conditions: Very nice skiing on settled storm snow with nice big dendrites still intact on the
We were looking for the advanced faceting on the top of January crust, but did not find any at our pit
locations. Buried surface hoar on top of Feb 7 was giving repeatable high strength results with no
propagation propensity, This urface hoar was mostly lying flat and tricky to identify without good
macroscope. We measured temperature gradient around the crust, 0.7 deg/10cm, not enough to
drive faceting process at the moment.
Magnum treeline aspect NW at 2200′ elevation, 19 deg slope
Weak layer: 2-3 mm buried surface hoar, 45 cm from top, 15 cm above crust.
Test results:3x CT27 RP, ECTN21 RP.