AVALANCHES: We skier triggered two persistent slab avalanches failing on the Jan 11 surface hoar layer, one of which sympathetically triggered another slide, on N to NE aspects near treeline on Peeler Peak. The slides were 1 to 1.5 feet deep. One failed 500 feet wide and sympathetically pulled out another slab about 200 feet away. They were on small features and ran roughly 150 vertical feet. SS-AS-R3-D1.5-O, SS-ASy-R1-D1-O, and SS-AS-R2-D1-O. Interesting notes: 1.) They were both triggered by the second skier from low on the slope, after the first skier had jumped around on the slopes attempting to trigger them. 2.) A large portion of the largest slide ran on slope angles below 35 degrees, with the slab pulling out on a slope as low as 20 degrees.

WEATHER: Calm to light winds, warm, few clouds.

SNOWPACK: South aspects: Multiple layers of wet crusts and facets to the ground on N/BTL slopes. As we approached ridgetop, there was ~3″ of wet recent snow that was easily sluffing on steep pitches.

North aspects above treeline: The slopes we observed were mostly wind scoured with large sastrugi features. A few crossloaded pockets. No signs of instability on steep slopes.

North – East aspects near treeline: Snow profiles on Peeler Peak and on Schuykill Ridge showed the Jan 11 surface hoar layer 35 – 40 cm deep, propagating in extended column tests (ECTP M, sudden collapse, Q1). Deeper weak layers were indistinct and unreactive in tests. See profiles

North-Northeast aspects below treeline: As we descended in elevation, the slab over SH lost cohesion due to faceting and was shallower in depth (<15 cm thick), and the surface hoar became spotty in distribution in semi-gladed terrain. The snowpack felt entirely faceted with the exception of a few isolated pockets of wind-stiffened snow.  Full trapdoor skiing at lowest elevations.  No signs of instability on steep slopes.

UPLOADS:

Bed surface with surface hoar still sitting on it.

Crown profile, Peeler Peak.  North aspect NTL

Profile on Schuykill Ridge, E aspect NTL

WEATHER: Mostly sunny skies, very warm temps, minimal wind. Did get a skiff of snow Saturday night. Crazy.

SNOWPACK/AVALANCHE OBS (approach flotation issues): We dug at edge of rock glacier in WNW side of whiterock up copper creek. HS Ranged from 80-200cm with widespread surface hoar 10-15mm preserved 20-40cm deep under a 4F slab. Dec 13th slab was unreactive until an informal extended deep tap got full propagation after wailing on it several times. Several natural avalanches were observed off center of e. Face of gothic and ene face of baldy from weds/thurs storm/wind. Spookiest results were on snodgrass. Preserved SH 10mm, ECTP7, ECTP12… Both SP, on 26*, E-facing slope. Deferred to lowest angle terrain and skied 30* meadow directly below saddle. 6th skier got large collapse on descent, but no cracking observed. Adjacent to our descent, on Friday, 2 skiers looked to have remotely triggered a 100-150ft wide pocket, 12-18″ deep, that looked like a SH weak layer from a distance. Below treeline, slightly convex meadow.

SNOWPACK: Location: 30 Degrees N, 12:20, 28 degree slope: ECTP #5 SC Q1. Fracture 35cm down on a buried surface hoar (3-5mm) 148cm HS. Slab on top (4f) on BSH Slab below (fist). Isolated column above and resulted on the same layer with skier weight.

UPLOADS:

Snowpit

WEATHER: Mostly cloudy in the morning before becoming clear by 10am. Light wind with moderate gusts at ridgeline.

SNOWPACK: Wet snow surface to varying depths below 10,500ft, in relatively thick trees and on all aspects observed. Snow surfaces just above treeline where heavy wind effected and generally hard wind pressed slabs. Along the way I found buried SH 30-50cm deep every time I dug into the snow. Obviously these were targeted and ended up being a , below treeline slope on a west aspect and at near treeline elevations on north and northwest aspects. At 11,600ft with a wind affected snow surface on a north aspect ,the SH was 35cm deep sandwiched between 1f slabs. Test results on this interface where CTM SC and ECTP19 SC. Even with these results we didn’t observe any collapse while traveling through the terrain. We either didn’t find the right spot on the slope, I need to eat more cinnamon rolls and pack on some pounds, or we need a big snow storm to make this interface more active in the area we traveled.

AVALANCHES: Saw a small point release or two (R1 D1) from trees and rock bands.

WEATHER: Hot! Gusty W winds on ridgetops, hardly noticeable elsewhere. Clouds slowly built throughout the day.

SNOWPACK: Just about anything you can imagine. On a small lee slope near TL I found everything from a supportive melted crust on more E-facing slopes and non supportive full depth facets on N-facing slopes that were sheltered from the wind. Slopes in between were supportive and showcased a nice surface hoar layer around 3-4 inches from the snow surface. Produced a clean Q1 shear on some baby burping. (Isolate a column and toss it up and down lightly). Snowpack was around 120 cm and deeper with some spots so supportive that I couldn’t push a pole through (these were more N-facing but likely benefited from the wind).

UPLOADS:

AVALANCHES: None.

WEATHER: Warm, clear, no wind.

SNOWPACK: Low angle south aspects held wet grains/ wet facets to the ground. Isothermal snowpack, 50 cm deep or less. Ski pen was nearly to the ground.
North and northeast aspects held entirely faceted snowpack, with about 2-4″ of DF at the surface. Boot pen to the ground, ski pen nearly to the ground. Melt-freeze crusts formed as far as 70* ENE aspect on steep slopes. Further north still dry.
I dug a pit below a heavily windloaded ridgeline, NTL type of snowpack. The new persistent slab over Jan 30th facet layer is 20 cm thick, and was unreactive in the pit, but produced localized cracking about 5 feet wide. The December 13th facet layer was 40 cm deep under a 1F slab, still propagating under moderate loading steps (ECTP15), and the depth hoar failed while isolating the column but this wasn’t a repeatable result, about 100 cm deep. This structure was isolated to just below ridgeline. About 20 yards downslope, it abruptly changed to fully faceted snowpack, with now persistent slab concerns.

UPLOADS:

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