Beckwith Pass and Kebler Corridor

CBACCBAC Observations

Date of Observation: 12/13/2022
Name: Eric Murrow

Zone: Northwest Mountains
Route Description: Kebler Pass road to Horse Ranch Park then up Cliff Creek route to Beckwith Pass.

Observed avalanche activity: No
Avalanches: non observed, visibility obscured views of the east end of East Beckwith or any other steep terrain in the area.
Weather: Overcast skies, moderate winds blowing west to east down the Kebler Pass corridor, light snowfall from 11am to 3pm. Storm totals ranged from 9 to 12 inches from Kebler Pass to Beckwith Pass. Snowfall rates during the day were light enough to be offset by the settlement in the storm snow already on the ground.
Snowpack: Near Beckwith Pass, I measured 11.5″of storm snow with .75″ of snow water equivalent. I dug a couple of profiles below treeline and found a snowpack that ranged from 100 to 130cm. Snowpack tests showed moderate propagating potential on basal facets. Given that the slab at this location (see photo) was nearly pencil hard, I think the .75″ of water in the storm snow had made the Persistent Slab problem more sensitive to the weight of a person, but not nearly enough to produce natural activity outside of highly drifted leeward features at upper elevations. I didn’t experience any collapsing while snowmobiling or while stomping through the slab directly above suspect test slopes. Due to slab thickness, around 90cm, and with a hardness near Pencil at the bottom of the slab, I would not really anticipate signs of instability in sheltered terrain until I found a trigger point. I also did not find any buried surface hoar beneath the storm snow in several suspect locations. I was able to produce cracking up to 15 feet in fresh, shallow drifts on lee features below treeline.

Photos:

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Red Lady Collapses

10webCBAC Observations

Date of Observation: 12/13/2022
Name: Cosmo Langsfeld

Zone: Southeast Mountains
Route Description: Red Lady Skin Track-Red Lady Glades

Observed avalanche activity: No
Avalanches:
Weather: Overcast, Light snow, light wind up high, calm down low.
Snowpack: Broke trail up Red Lady skin track. Quiet until near tree line. Small collapses on pillows behind tree fences near tree line. Isolated collapses and short shooting cracks on hardish windboard on windward terrain just below ridgetop above tree line. One larger collapse on low angle west-ish facing terrain in a meadow around aspens lower down on the descent.

5745

West Brush Creek

CBACCBAC Observations

Date of Observation: 12/12/2022
Name: Eric Murrow

Zone: Southeast Mountains
Route Description: Brush Creek TH to West Brush Creek. Tour in the Union Chutes area.

Observed avalanche activity: Yes
Avalanches: A handful of natural avalanches from last week were observed on east and northeast terrain near and below treeline.
Weather: Cloudy skies produced light snowfall from 1230 to 2pm with sporadic snow through 330. Accumulations less than an inch. Southwesterly winds drifted snow at ridgetop with light loading onto easterly alpine start zones.
Snowpack: The snowpack remains fairly shallow, less than 2 feet, below 9,500 feet near the confluence of Brush and West Brush Creeks. Snow depth increased as I traveled the few miles up West Brush Creek. Snow depth near the valley bottom by Teocalli, around 10,000 feet, on east and northeast terrain was about 90cm and slowly increased to around 105cm around 11,200 feet. Close to valley bottom, I produced some moderate size collapsing. Near 11,000 feet and above I struggled to get a collapse even with booting into the weak layer but finally got one loud, rumbling collapse after numerous attempts. Snow pit tests produced moderate propagating test results on the basal facets (see photo).  Fewer signs of instability than I expected, but the same poor structure above the untrustworthy basal facets.

Photos:

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Trailhead Day #3-Slate River TH

CBACAnnouncements, Events, News

Join CBAC and Irwin Guides for this special event with free beacon skills training. Come by anytime from 9:00am to 2:00pm for the latest information on snowpack, conditions, local maps, and snacks or to chat about anything backcountry related. At 10:00 am, 11:00 am and 12:00 pm, Irwin guides training staff will be available for free 1-hour beacons skills training. No sign-up is necessary, show up with your over-snow gear and rescue equipment. If you don’t have rescue gear, we will have beacons, shovels and probes on hand to borrow. Email cbavalanche@gmail.com with any questions about the event.

Getting more stubborn

CBACCBAC Observations

Date of Observation: 12/11/2022
Name: Zach Guy

Zone: Northwest Mountains
Route Description: Pittsburg Rollers area, up to 10,500 ft on north to northeast aspects.

Observed avalanche activity: Yes
Avalanches: Nothing new today. Filling in some previously undocumented persistent slabs from the 12/6-12/8 cycle. See photos.
Weather: Unseasonably warm and sunny
Snowpack: Widespread 1mm to 3mm surface hoar below about 10,000 feet on shady aspects, with minor near surface faceting elsewhere on the snow surface.
After venturing away from the regularly traveled areas, we tried getting collapses by skinning, stomping skis, and then punching boots through the slab a few times. Only one of the boot pen attempts produced a rumbling collapse. Tests produced hard, propagating results on a F+ layer of rounding facets buried below an 80 cm slab up to 1F hard. The failure occurred just below the thin rime/rain crust that formed back in November. See pit.

Photos:

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Wolverine Basin

10webCBAC Observations

Date of Observation: 12/11/2022
Name: Ian Havlick

Zone: Northwest Mountains
Route Description: Up from Gunsight bridge to upper Wolverine Basin.

Observed avalanche activity: Yes
Avalanches: Pretty much a war zone starting from
Climax chutes all the way to top with lots of little steep convex features having failed since the snow stopped 3 days ago. Lots of road cuts and larger features- anything over 35 degrees highly suspect
Weather: Clear, calm, cold
Snowpack: Snowpack structure similar to other observations submitted, F>1F slab resting on 20cm of large grained depth hoar. Most notable observation was widely distributed 4-6mm surface hoar on aspects traveled (N-NE-E) from 9000-11000ft. Will be worth watching with incoming snow tonight.

Photos:

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Baxter Basin

10webCBAC Observations

Date of Observation: 12/11/2022
Name: Alex B

Zone: Northwest Mountains
Route Description: Standard uptrack on the east side of the creek into baxter basin and up to the south side of cascade.

Observed avalanche activity: Yes
Avalanches: No cracking, collapsing or new avalanches observed. Isolated natural cycle in alpine terrain features in the last 48-72hrs.
Weather: Clear. Calm valley winds gusting to moderate from the SW at ridgetop. Mild temps with strong solar input.
Snowpack: Targeted one shallow slope and one deeper terrain feature. HS ranged from 90-170cm.
NW 10200′ moderate results from multiple handshears failing on 2-3mm well-preserved graupple down 45cm.
NW 10400′ CT22 RP down 65cm failing on the 2-3mm graupple.
The slab above this interface progressively stiffens to a 1f slab above and to a pencil hard slab below. The bottom 15cm of the snowpack are large grained facets.

5739

Tree rumbling Collapses

CBACCBAC Observations

Date of Observation: 12/11/2022
Name: Zach Kinler

Zone: Southeast Mountains
Route Description: Up Anthracite Mesa via Washington Gulch TH

Observed avalanche activity: No
Avalanches: No new avalanches observed
Weather: Sunny and pleasant, calm winds.
Snowpack: This is a zone that has seen no traffic so the slab/weak layer was unmolested. I got rumbling collapses in every open area and some areas within the trees. Most often these collapses shook the snow off of trees in the surrounding area. A pit at 10,800′ on an East aspect produced and ECTP13 on 2-3 mm facets near the ground under a 45cm slab up to 1F. Stomped above a couple of steeper slopes with no results however these appear to have avalanched in early December with around 10 inches of low-density snow in the bed surface.

 

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5738

Avalanche

10webCBAC Observations

Date of Observation: 12/11/2022

Zone: Southeast Mountains
Route Description: Red lady bowl

Observed avalanche activity: Yes
Avalanches: D2-3 R2-3 remote triggered SE side of bowl from the SW side of bowl. Was not carried buried or injured. Really close call.

Photos:

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