Wind loading, localized cracking in wind crust
Observation: Turnagain
Location: Tincan
Standard route to 2500′ and then skinned north to CFR ridge. Objective was to dig in a shallower spot on north aspect and observe the winds at the Pass.
Observer Comments
Weather
Partly cloudy
Temperatures in the mid teens on the ridge, mid 30Fs at road level
NW winds picked up around noon gusting into the 40-50s.
No precip
Snow surface
Melt-freeze crust to 2200' becoming thinner and more breakable with elevation gain. Southerly aspects had a thicker melt freeze crust. There was a trace - 2" of new snow over the crust. Above 2200' wind crust, sastrugi and pockets of softish wind slab. Winds were loading from the both the south and the north.
Snowpack
Dug one pit @ 2660' (see photo and video below). We dug where the slab was thinner in a more scoured area. Jan 21 buried surface hoar was 70 cm below the surface and reactive in both CTs and our ECT. Stubborn to trigger but scary consequences with a thick, hard slab.
melt-freeze crust @ 1000'
Surface @ 1000' at 3 pm
Surface conditions @ 1700'
thin melt-freeze rust @ 2000' and wind effect
Wind crust cracking @2200'
Tincan anti-tracks
Magnum NW ridge
Wind loading Seattle Ridge
Wind plumes on Wolverine
Pit @ 2660'