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.

Avalanches: Did see 6-10 D1-1.5 dry loose avalanches off steep terrain on east, south and west terrain ATL, looking like some initiated off warming rock bands.

Evidence of many wide slides on steep east facing terrain and did observe evidence of a few west facing crowns in steep aspens that ran around xmas. Some of the crowns observed looked a little more recent…possibly wildlife triggered…

photos highlight slopes that may hang in the balance still or may re-activate with future loads in a more destructive avalanche…steep convexities slid, but more planar slopes did not…
Weather: Clear, cold with light northerly breeze with visible transport off high peaks (teo, whiterock) at times. High around 20ºF. Morning temp at TH at 10am was 2ºF.

Snowpack: Generally shallow, weak, and faceted. with average HS 50-80cm.

One pit today, 70cm, 33* slope, SW facing NTL. Ct14 SC on basal depth hoar 4-6mm, but skinned 38*+ terrain with no signs of instability. I think persistent grains definitely exist on all aspects and elevations but slab has eroded. Sledding was challenging with track augering badly in shallow snowpack, don’t take your thumb off the throttle!

fresh D1.5 loose avalanche initiated off warming rock bands on SE facing steep slope on Teocalli

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Avalanches: On steep slopes that had avalanched previously, we skier triggered two sluffs that ran far, gouging to the ground, and could have knocked you over or buried you in a terrain trap. L-AS-R1-D1.5-O
Weather: Few clouds, cold temps, light northerly winds without snow transport.
Snowpack: About 4″ of settled storm snow, over crusts on southerly aspects (up to 2″ thick on steep S, thinner on SE) and facets on northerly aspects. No signs of wind loading or slabbiness in new snow.
Most paths on the northern half of the ridge ran naturally last month with crowns still visible, leaving a structure comprised of 1 -2′ of low density, faceted snow over ground/bedsurfaces. Dug one crown profile on a windloaded NE aspect near treeline, from an Xmas cycle slab avalanche (Photo #1). 95 cm of slab, mostly 1 finger rounds, over fist hard facets. Propagating results. (ECTP 16, Q1 SC, 95 cm deep) Dug another profile on a SE aspect near treeline, 28 degree slope (Photo #2). About 70 cm of faceted 4F to F snow, over 4F moist facets. No test results over the basal layer, but clean propagation in facets below the thin crust near the surface. Not an issue now but could be in the future. (ECTP1, Q1, SC, 10 cm deep).

NE aspect near treeline. ECTP16, Q1, SC results on fist hard depth hoar 95 cm deep.

SE aspect near treeline. No results except propagation below the near-surface crust.

Avalanches: Saw a small SS -AS -r1d1 on SE aspect on cascade. occurred on steep rolls ~40*.
Weather: Mostly cloudy with occasional light snow. Visibility limited at times. Light winds with occasional light gusting.
Snowpack: New snow had yet to settle much with little to no slab formation in top 30cm. Ski pen around 25cm. Terrain in area toured showed persistent slab structure. Total depth was between 130cm – 200cm. Beneath new snow was a very supportive slab that was generally 1f density ranging in thickness from 80cm – 150cm. This strong slab was bridging well developed facets at ground. Structure was a bit concerning. Skied terrain up to ~38* without incident.

Avalanches:
Weather: High around 20F small period of S-1. Overcast sky most of the day. Light winds from the N/NE, partly cloudy with a few snow squalls and a nice sunny period in the afternoon.
Snowpack: Ob#1: HS averaged 80-90cm. We dug 2 pits, 28/32* slopes and did several CT’s. We had consistent results: CTH (21/22) with most releasing at and just above the DH layer on the ground. One result released 10 cm just above the DH layer (30 cm from the ground) with a SC. We had 1F hardness in our mid pack which made for very supportive skiing.
Ob#1: HS ranges from 75-88 cm. In our pit we got moderate results on CT tests releasing on the
DH layer (2-3 cm) on the ground. Got no results on ECT test. Still a 4F harness soft slab but it is faceting out. Pit was on a NE aspect on a 26 degree slope.