Avalanches: Sensitive shallow windslabs 6-8” forming across westerly terrain of UWW, EBM, SBM, considering shallow depth, propagating widely, easily mitigated with any kind of traffic immediately.
Weather: Cold, snowy, blustery day.
Snowpack: appears settlement has flattened out at 46. Boot pen is not to ground anymore, and ski pen ~10-20cm. Light low density snow, 2” last night, 1.5” during day.

Avalanches: No new avalanches observed since Christmas cycle.
Weather: Cold temps (~5 to 10*F). Calm to light westerly winds. Light snowfall tapered late afternoon, about an inch of accumulation during the day. Overcast to broken skies.
Snowpack: 5 or 6 rumbling collapses below about 10,200 feet, becoming quieter as we gained elevation to near treeline. One pit on an ESE slope below treeline had 85 cm of slab over fist hard facet layer. The slab was 1F in hardness near the bottom, up to fist hardness at the top, leaving a sense of “It feels good and stable” while skinning. 3x propagating results in ECT, moderate to hard, Q1 SC. Another pit on a SW aspect near treeline showed a 100 cm slab over a thin, friable crust (1cm thick, 1F hard), over a fist hard facet layer. Slab collapsed on isolation (ECTPV) on first test and after 30 taps on second test (ECTP30 Q1, SC). Quick pit in an old bedsurface from Christmas cycle on an E aspect near treeline showed a mix of meltfreeze crusts and pockets of old facets at the ground, with about 45 to 50 cm of recent snow above, 4F to F hardness.  See VIDEO

Hand hardness profile on ESE aspect below treeline. Repeated propagating failures near the ground on fist hard facets

IMG_5414

Avalanches:
Weather: Calm to light in general, gusting to Moderate NW winds on Ridgetops
Snowpack: SNOWPACK/AVALANCHE OBS:
No signs of instability.
HS 100-130cm
6-10cm 4F+ windslab only on the ridgetop @ 11,600
ski pen 10-15cm
Evidence of heavy wind scouring along the high elevation ridges (12,0000 and up) from NW/W loading onto E/SE

Weather: Occasional light snow flurries, mostly cloudy sky, calm wind.
Snowpack:

South, Southeast BTL
Due south slopes had a nice 1-2cm crust at the surface on slopes generally over 25 degrees, while these crusts started to fade as you moved to southeast slopes. BTL, the snowpack consisted of the Christmas storm snow sitting on the ground. Around 10,300ft and above, this same storm snow was sitting on a variable soft crust just above the ground, surrounded by facets. Here HS was about 50cm and one column test produced a CT4, sudden but irregular fracture. This snowpack structure looked concerning but was variable and inconsistent across the slope. We traveled on these slopes for a long time at about 35degrees with no other obvious instabilities observed. Also, didn’t observe any structure at NTL south or southeast start zones.

Northeast NTL/BTL
Observed widespread old natural avalanches in start zones spanning east to north. After a short tour across a few avalanche paths, it seemed some 80% of avalanche terrain had already released down to the facets near the ground during the last cycle. Most of the hang fire that was left had already cracked and buckled. We traveled across a few pieces of hang fire where the structure remand very concerning, while the avalanche problem felt very stubborn. Only one collapse was observed while in these areas. Just below a crown at 12,300ft the HS was about 45cm with about 35-40cm of that as unconsolidated new snow that would have fallen during the later half of the Christmas Storm.

Avalanches: About 10 natural avalanches observed in this area from recent cycle on SE, E, NE aspects. SS-N-R2-D1.5-O.
Weather:
Snowpack: Short tour, got 2 large, rumbling collapses in flat terrain and numerous localized collapses. Persistent slab is thinner here, 14-18″ on average. Supportive on skis but easy to penetrate through to weak layer. Seems like propagation potential only exists where slab is a little thicker or stiffer, otherwise collapses wouldn’t carry across slope as slab fractured in thin spots.

Avalanches: No signs of current avalanche activity in the area we were skiing . Some old evidence of activity on steeper slopes .
Weather: Calm, partly sunny with high clouds
Snowpack: No signs of instability . Snowpack was quite supportable . Surface facets apparent from cold temps

Avalanches:
Weather: Increasing clouds; calm winds; cold temps (-1F at 0915 @ TH /// 10F @ 1400 @ TH)
Snowpack: HST is definitely settling rapidly and consolidating into a soft slab. Ski Pen while breaking trail all day was about 20cm, while Boot Pen was full depth. Overall HS in this zone was 80-110cm. New surface hoar growth also observed on lower valley slopes. Got two thundering collapses (shaking snow off surrounding trees) when traveling in untouched low angle NE facing timbered terrain, but other then that, we saw no other signs of instability on other aspects, despite traveling on slopes just touching up into the 35* zone. But the Spx structure here was also mostly all F and 4F recent storm snow over either bare ground, or very very small thin depth hoar pockets, and seemed to lack any propagation propensity or strong over weak layering in general. Hand Shear and Shovel Tilt Tests produced no results. Things are changing fast though, as the rapid settlement continues, and there could be more of a cohesive slab on these aspects by tomorrow even, if it stays warm and sunny.

Some very heavy caveats come with this diagram.

1. Observations are likely biased based on aspects that are visible from easily accessed points within our zone.  For instance, we don’t have good views of as many NW facing avalanche paths from town as we do E or NE.
2. Frequency of natural avalanches is not necessarily a good indicator of where you are more likely or less likely to trigger an avalanche as a human.  Some slopes have the right ingredients for human triggers but didn’t see enough loading for natural release. West facing terrain is a good example of that.

Avalanches observed 12/21-12/28 failing on persistent weak layers. Produced by Zach Guy