Localized cracking in thin wind slabs.
Observation: Hatcher Pass
Location: Stairstep
Jostled for a parking spot at the bottom of the road run. Ascended Stairstep to 3900′. River crossing was easy thanks to skin track pioneer and HPAC Advisory Board member extraordinaire Andy Dennis.
Observer Comments
Weather
Moderate SE wind transporting snow all day above 2500'. Temperature around 20 degrees F.
Snow surface
Snow surface varied between boot top settled powder to breakable wind crust. Early season conditions exist below 2500', with exposed vegetation poised and waiting to catch a ski tip. Surface hoar in sheltered areas below 3000'.
Snowpack
Below 3500' the snowpack is mostly settled powder sitting on a mass of basal ice. On N to NW aspects a breakable wind crust or supportable wind slab can be found sitting on buried near surface facets. First noticed the slab at 2800'.
Dug at two elevations:
3670':
Pit 1: N Aspect, 32 degrees, HS=75
ECTPV, ECTN4 on 10 cm wind slab
ECTP25 x 2 down 40 cm on 3mm chained facets above MF crust below 1F wind slab
Pit 2: N Aspect, 28 degrees, HS = 65
ECTP24 & ECTP26 down 53 on 2.5 mm chained facets below MF crust
CT12SC on basal 3mm basal facets at ground
3900':
Pit 1: NW Aspect, 18 degrees, HS = 110 cm
ECTPV down 5 cm on wind slab
ECTP24 down 65 on 1.5 mm facets above MF crust
Pit 2: NW Aspect, 19 degrees, HS=73 cm
CT26SC & ECTP13 down 40 cm on 2mm facets between rain crust and MF crust
Pit 3: NW Aspect, 17 degrees, HS=60 cm
ECTN3, ECTN13, CT16SC down 30 cm on 2mm facets above MF crust
Crossing the Little Su is becoming reasonable, allowing access to Arkose Ridge
Low snow and vegetation below 2500'
Wind affect above 3500'
Old skin track filled in by wind transported snow
Pit at 3670 ft, N aspect
Pit at 3900 ft, NW aspect