BC Zone Observation Report
Tuesday, January 12, 2021 at 12:00 AM
Gunnison
Details
Date:
2021/01/12
Observer:
Zach Guy
Organization:
CBAC
Location
BC Zone:
Gunnison
Area Description:
Zone: Northwest Mountains
Route Description:
Location: Slate Aspect: North East, East Elevation: 9,000 to 11,400?
Weather
Weather Description:
Weather: Inverted temps, thin broken cloud cover in the afternoon, calm winds.
Snowpack
Snowpack Description:
Snowpack: In the windsheltered terrain that we traveled in up to 11,000 feet, the slab has mostly faceted away. There is some residual 4F or 4F- faceted midpack. Test results on this structure were unreactive. We tested a windloaded terrain feature near ridgetop (11,300 feet). The slab is noticeably denser (up to 1F midpack), and the test produced hard propagating results. In some terrain that avalanched in mid-December, the snowpack is entirely fist hard, large grained facets. The structure is quite weak, and now capable of producing full-depth sluffs in steeper terrain.
Avalanches
Avalanche Description:
Avalanches: In a path that ran in mid-December, we skier triggered a long-running facet sluff that gouged to the ground. It ran about 1,000? vertical feet and entrained about a foot of weak faceted snow, about D1.5 in size. Good communication from partners watching from ridgeline prevented this sluff from surprising the skier. It started off very small and slow but picked up quite a bit of speed and punch by the end.
Date
Location/Path
#
Elev
Asp
Type
Trig
SizeR
SizeD
2021/01/12
Schuykill Ridge
1
TL
NE
L
AS / u
R1
D1.5
Date:
2021/01/12
Observer:
Zach Guy
Organization:
CBAC
Landmark:
Schuykill Ridge
Media
Video
January 12, 2021: Persistent slab structure is more concerning on higher, windloaded terrain
Images