Avalanches: One fresh looking D1.5 or D2 debris pile below a south facing slope above treeline, near Pearl Pass, viewed from a distance. Start zone was obscured by cliffs, but assuming it was a natural wind slab from the past few days. More small skier triggered facet sluffs below treeline.
Weather: Thin clouds increased through the day from few to broken. Light winds with no transport. Cold temps at valley bottom, mild temps above treeline.
Snowpack: See video. Surface hoar below treeline and near surface facets on all aspects/elevations, beat up by winds above treeline. The surface became moist on southerly aspects near treeline today, with small grained facets above.

Isolated pockets of recent windloading produced cracking up to 6″ deep on S/SE rollovers above treeline

Near and below treeline, the snowpack was shallow (<70cm) and entirely faceted (F to 4F) Persistent slab was unreactive ( ECTX and ECTN failures) in tests, even on leeward, deeper aspects (NE, E), We could find isolated pockets of discontinuous persistent slab structure within the first 20 feet of windloaded ridgelines, but the slab did not extend down slope. Above treeline on E aspects, we found 1F to Pencil hard slabs (70cm thick) over 3-4mm F+ hard depth hoar in our pit with propagating results (ECTP21, SC). We found similar structures identified by probing on other slopes facing E and NE above treeline. Difficult to tell how continuous the PS structure is on ATL start zones…obvious variability due to winds but I didn’t want to venture onto anything steep. S, SW, and W aspects N/ATL were visually shallow and you’d be hard pressed to find a slab anywhere; lots of rocks or bushes showing. We skied a steep south aspect ATL with no signs of instability.

Faceted slab. NE aspect NTL. ECTN failure.

ATL, E aspect. 1F to P hard slab over 3-4mm depth hoar. ECTP21, SC

Cracking on isolated wind drifts, 6″ deep

Surface hoar below treeline

Thin coverage on W, SW, S aspects N/ATL. West aspect NTL shown here

Avalanches:
Weather: Clear & Cold. -7F @ 9:00 / 8F @ 1430 at TH. Light down valley N winds in afternoon, ridge top blowing from NNW all day, calm in valleys. .
Snowpack: Lots of needled surface hoar growth observed on all aspects of the compass, and throughout all elevation bands throughout our tour today. Predictably skier triggered 2 separate Loose Dry Snow slides (R1/D.5) on 35* terrain; full-depth facet sluffing to the ground where the slope previously avalanched during Xmas cycle. Slow moving and small entrainment. No other instabilities noted while traveling on slopes

Avalanches: Observed evidence of 4-5 small (D-1) wind slab avalanches in south facing slopes, above treeline around 11k feet. In our group, a skier triggered a small wind slab while bootpacking on a SE slope about treeline on a 38 degree slope. It was about 20′ wide and up to 6″ deep.
Weather: Clear, Cold, Gusty.
Snowpack: Although it was cold, snowpack was moist.

Avalanches: Small skier triggered windslab avalanche on Ruby at approx. 12,000 ft. on a 35+ degree, SSE slope. Slide broke near rocks during our initial bootpack approach and propagated approx. 25 ft. with an eventual path approx. 60 ft. wide and 90 ft. long. Fast moving bed interface, some slabs were 6-8″ thick. Skier was caught but not carried or buried.
Weather: Cold, sunny, mostly blue skies, windy on the ridgelines and summits
Snowpack: Snow was variable, breaking trail it felt supportive until higher elevation, that’s when we got our warning

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Avalanches: Spotted about 3 or 4 recent natural wind slab avalanches (D1 in size, estimated last 24 hours) on S and SE aspects above treeline in the northern portion of our zone. Skier triggered 2 sluffs on steep, shady terrain N/BTL on slopes that had previously avalanched. D1.5 in size, gouging to the ground. See photo.
Weather: Thin, few clouds. Cold temps. Light to Moderate north winds. Plumes off of northern portion of our zone this morning; then a lull mid day, then pluming again late this afternoon across whole zone.
Snowpack: About 3-4″ of recent new snow. No signs of wind effect except below south/southeast facing ridgelines ATL, where we saw top-heavy windloading with minor cracking a few inches deep. Dug 5 pits on NW to NE to E aspects near treeline across 3 different basins to check out reactivity of PS problem.
1.) NW aspect. HS 165, 105 cm slab (1F to 1F+) over basal facet layer (4F+ hard, 1.5mm rounding facets) ECTX and no signs of failure with additional loading steps.
2.) NW aspect. HS ~50 cm. Faceted snow throughout (4F to F). ECTX, slab crumbled.
3.) NW aspect. HS 150. 1F slab over basal facets (4F-, 2mm facets). ECTX, but SC failure with additional loading
4.) E aspect. HS 125. 1F slab over basal facets (F+, 2 mm facets). ECTX, but SC failure with additional loading
5.) NE aspect HS 115. 1F slab over basal facets (F, 2-3 mm facets) ECTP24, Q1 SC.

Skier triggered sluffs on steep, shaded terrain that has avalanched previously, leaving shallow faceted snowpack.

Avalanches: Nothing since Christmas storm. No cracking, no collapsing.
Weather: The sun was warming, but most of the day was frigid. Light winds in the morning increased from the NW. Partly cloudy skies and maybe it snowed a little? Or maybe it blew outta the trees.
Snowpack: Skied south/south east around 11 am. Denser snow with a crust layer about 6-8″ under the surface and a solid base below that up to 140 cm. Skied north/northeast (45 degrees on compass), around 1:00. Cold smoke top 12″ with a persistent slab below. Basel facets found in probing in most areas even where previous avalanching had occurred.
SSE slope at 2pm became moist despite cold temps. New snow consolidated to about 4″ over a previous crust. Solid below this with no other crusts found with probing.