Upper East River Basin/Gothic

CB Avalanche Center2016-17 Observations

Location: Crested Butte Area
Date of Observation: 02/28/2017
Name: Steve Banks/Mike Soucy
Subject: Upper East River Basin/Gothic
Aspect: North East, East, South East, South, South West
Elevation: 9000-11100

Avalanches: About 10″ of new snow since yesterday morning. Lots of small, localized collapses underfoot throughout the day on all aspects travelled on. 1 test profile showed HS 230 cm with 35 cms of newer snow over crust facet sandwich. ECTX but prying with the shovel popped the slab off on 1cm thick .5 mm facets between 2 crusts.
Remote triggered a D2 and a small D1 on the NE slopes of Snodgrass skiers left of the low point of the saddle. Triggered from a small bench about 200′ away from the slope. 200′ wide running about 600 vertical with a crown of up to 53 cms. Weak layer was buried near surface facets. 35 degree slope at 10,400′ Crown investigation showed CT 21 SP failing on the same NSF.
Also noted a large D2.5 off of the East face of Gothic initiating just below the very large cornice on the summit ridge and running to about 10,200 just above the valley floor.
Watched a release out of very steep terrain, East facing above Copper Creek likely windslab and maybe D2. Noticed 2 other pockets, mid elevation roughly 10,600 with minimal propagation and D 1.5.
Peak of instability seemed to come around 3 pm today. Surface snow became noticeably stiffer in the afternoon.
Weather: S-1 most of the day with periods of S3. Increasing winds through the day as snow decreases with strong gusts in the afternoon. Winds from the West and high temp of -7.
Snowpack:

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