Windslabs near Pittsburg

CBAC2014-15 Observations

GUIDE(S): Jeff

DATE: 2015/01/05

ACTIVITY: Ski tour

LOCATION: Commando Trees

ELEVATION: 9600′ – 10,400

ASPECT: NW-N-NE

WEATHER: Variable/Overcast, flat light, dry most of the day, Strong to Extreme, mostly N channeled down valley

SNOWPACK/AVALANCHE OBS: sled parking (valley floor along stream) got avalanched by a D1 windslab 30cm thick that formed while we were touring! Fairly recent slab D1.5 under the cliff band of Schuykill peak above pittsburgh rollers. Schuykill looks stripped in many places & very thin, highly variable. No other signs of instability on surrounding alpine peaks

In Old Growth timber: consistent & stable pack of ~120-135cm of well bonded snow.
Bonding Tests:
Location: NW, large living room sized opening in forest @ 10,400. Lots of tree bombs evident in the pit. 25 degree slope, ski pen 10-15cm. boot pen 30cm. Progressive hardness downwards except a 1 hardness change @ 70cm down on rounds/rounding facets interface

DTH on ground (moist, dense (4F) cohesive facets, sticking to leaves, non repeatable)
DTN
CTH @ 70cm down on rounded slab (1F) & rounding facets interface (4F), Q2 (RP)
CTN
ETCX

Skied slpoes up to 50 degrees with no instabilities