Upper Slate, Baxter Basin

CB Avalanche Center 2015-16 Observations

Location: Paradise Divide Area
Date of Observation: 11/21/2015
Name: Ian Havlick
Subject: Upper Slate, Baxter Basin
Aspect: North, North East, East, South East, South
Elevation: 9500-12000

Avalanches: Saw numerous small wind slabs in extreme terrain on NW-N-NE facing, unsupported slopes in Baxter Basin, and below Schuykill Peak. Investigated largest, most significant slide in the area just north of Richmond Peak, in a feature some people call the “Martini Glass Coulior” or “chicken leg.” Looked like a few days old, natural avalanche triggered by rapid windloading. Ran over 1000ft. After investigation, looked like it failed on the Nov. 10th melt-freeze layer that formed from warm temperatures on this NE-SE facing start zone. ECT tests had no result. snowpack fairly deep here, 140-180cm deep, mostly 1F hard snow with moist facets near the ground (1-2mm).

Weather: Clear, cold throughout day. Light westerly winds above treeline all day. Solar radiation was strong enough to warm ourselves, but not to form surface crusts or moisten southerly snow surfaces.

Snowpack: Mixed bag.

BTL: Still thin, generally weak. Yesterdays dense 4″ of graupel added to lower elevations supportiveness while skinning and sledding. ski penetration ~20cm, never to ground unless in very shallow, rocky areas. HS ranged from 40-75cm.

N/ATL: Slab and snow depth increases with elevation. HS ranged from 65-150cm+. Strong NW winds last several days really moved and hardened snow above treeline, with 1F-P hard, slick slabs widepread on NE-E-SE-S facing slopes. Yesterdays graupel was being moved/rolled easily downslope with light winds, no slab formation within this most recent surface snow yet. Numerous large collapses felt and heard on flat areas NTL, but no signs of current instability ATL observed. Snowpack tests throughout day did not produce significant results, and moist facets near the ground were present everywhere we dug (NTL and ATL).

up close “martini” avalanche and minor portion of debris that hung up on small bench
“Martini glass” coulior windslab overview photo (all of debris not visible)