Hot storm slab off of Teo today, plus recent persistent slab activity

CBACCBAC Observations

Date of Observation: 03/13/2023
Name: Zach Guy

Zone: Southeast Mountains
Route Description: West Brush Creek. Traveled mostly on east and northeast aspects to 11,600′

Observed avalanche activity: Yes
Avalanches: Observed a large storm slab (D2.5) run this afternoon off the south face of Teo. The slab initiated as a relatively small pocket on a southeast aspect and then triggered a much broader, thicker crown on a cross-loaded terrain feature facing south that subsequently ran to valley floor.
Several very small dry loose and wet loose avalanches ran throughout the day.
West Brush Creek drainage saw a fairly widespread storm slab cycle, D1-D2, likely Friday night-Saturday morning. Pics show the largest slides, though there were plenty more. In three of the S/SW gullies of Teo, storm slabs stepped down and triggered more destructive persistent slabs, D2.5-D3. The crowns were mostly filled in but I measured debris blocks as thick as 4 feet, pencil hard.
Weather: Few to scattered skies through mid-afternoon. Mild temps. Calm winds.
Snowpack: I didn’t measure storm snow totals, but they seemed on par with other areas, in the 2-foot range. Snow surfaces became moist to wet on everything without a northerly tilt, producing a few rollerballs and minor sluffs. We skied on several steep, shady slopes with no signs of instability. However, we did get a creek bed to calve off about 3-feet deep on a facet layer at valley bottom.

Photos:

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Gothic Weather

CBACCBAC Observations

Date of Observation: 03/13/2023
Name: billy barr

Zone: Southeast Mountains
Route Description: Gothic Townsite

Observed avalanche activity: No
Weather: Light snow Sunday, then a short wave after dark before scattered showers overnight with 6″ new and water a more reasonable 0.44″. Currently cloudy with a few small patches of what passes for blue (take what you can get) and calm (have to love that one). Current snowpack is winter deepest at 83½”
Snowpack:

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Mt Emmons BTL

CBACCBAC Observations

Date of Observation: 03/12/2023
Name: Evan Ross

Zone: Southeast Mountains
Route Description: Mt Emmons. 9,000 to 10,200. W-NE-E. BTL

Observed avalanche activity: Yes
Avalanches: 3 to 4 D2’s in the Climax Chutes and a few smaller avalanches. These all likely ran early Saturday morning. Couldn’t see any crowns in the start zones, so assuming they were storm slabs that entrained snow.

A couple of small point releases today on various aspects.

Weather: Mostly cloudy. Calm wind. Up to 2″ of new snow in the afternoon.

Snowpack: We didn’t find any signs of instability on this lower-elevation tour. Lots of settlement from yesterday, and yesterday’s crust that formed around most of the compass, appeared to have killed the storm slab problem in this location. A couple of small point-release avalanches that ran today in the climax chutes, and on a NE-facing slope at 10,400ft didn’t propagate in the storm snow. We did 1 ECT test at 9,600ft, NE aspect, 35-degree slope, and got ECTN results in the storm snow and at the old snow interface.

HST on yesterday’s crust was 4″ down low and 6″ at 10,200ft.

We ran into the Gunsight Moose on the descent. The Moose was hanging out on GB loop.

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Storm instabilities quieting down in Cement Creek

CBACCBAC Observations

Date of Observation: 03/12/2023
Name: Zach Guy

Zone: Southeast Mountains
Route Description: Traveled on various aspects of Cement Creek and Reno Ridge to 11,200′, as far up valley as Block and Tackle Trail.

Observed avalanche activity: Yes
Avalanches: The most notable avalanche in Cement Creek was the previously reported large slide that crossed the road between Warm Springs and Deadmans Saturday morning during the storm. This appeared to be a wind-drifted storm slab that entrained a large amount of snow (see photo); the main lobe of debris was about 10 feet deep and stopped just short of the road, with some debris washing across the road to the creek. I saw one other D1 storm slab below treeline and evidence of moving snow on steep roadcuts from the storm. Visibility of above treeline terrain was limited. No new avalanches today.
Weather: Mostly cloudy, with intermittent periods of moderate snowfall. About 3″ of new snow overnight and today. Light winds and no blowing snow.
Snowpack: No signs of instability while snowmobiling and skiing on numerous steep slopes. I was able to produce some localized cracking about a foot deep on a drifted slope after undercutting the feature first. Storm totals are 18″ to 24″ deep, fist to fist+ hard; stiffer and more upside-down on drifted features.
I was hunting for signs of persistent slab issues on shallower slopes and did not get any collapses or unstable results. On a WNW facing terrain feature, I found a structure that would be concerning with additional slab consolidation and snowfall: it was a 60 cm fist hard soft slab over 2mm, fist hard facets, ECTX results (slab crumbled).

Photos:

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Irwin Cat-Ski observations and control results

CBACCBAC Observations

Date of Observation: 03/11/2023
Name: Irwin Guides Cat-Ski

Zone: Northwest Mountains
Route Description: Irwin Guides cat-ski tenure

Observed avalanche activity: Yes
Avalanches: Avalanche observations: HST responsive to AE, unresponsive to AS
Long HS-AE-R1-D1.5-I DF (30cm x 10m x 135m)
Way Long HS-AE-R1-D2-I MF (30cm x 20m x 135m)
Thorton’s HS-AE-R1-D1.5-I MF (50cm x 20m x 115m)
Bender HS-AE-R1-D1.5-S DF (15cm x 10m x 125m)
Flaming Ferrari HS-AE-R1-D1-S DF (20cm x 5m x 50m)
Weather: “We are currently HST: 28/3.2″ with more snow in the forecast. We also cracked a 100″ base today, which is nice.

The latest round of precip came with an extreme SW wind event, which is less nice. Last night we registered 5 hours of wind gusts from 35-48 at our base area study plot at 10.4k.”
Snowpack: This wind event combined with a warming trend during the storm produced widespread hardness inversions that were responsive to AE, but not to AS. A most uninspiring structure.

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Kebler Pass corridor natural Storm Slabs – shared via Instagram

CBACCBAC Observations

Date of Observation: 03/11/2023
Name: Insta Gram

Zone: Northwest Mountains
Route Description: Kebler Pass Road obs

Observed avalanche activity: Yes
Avalanches: “Counted 7+ D1.5’s along Kebler corridor this morning between TH and Axtel skintrack – All on the South facing road cuts”
Weather:
Snowpack:

Photos:

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Cement Creek xc trail natural avalanche – shared via Instagram

CBACCBAC Observations

Date of Observation: 03/11/2023
Name: Insta Gram

Zone: Southeast Mountains
Route Description: Natural avalanche impacting Cement Creek Road/xc trail

Observed avalanche activity: Yes
Avalanches: “Hard to tell, but the big path in the heart of Cement Creek XC trail ran last night…looked like it wasn’t even from the very top from what I could see.”
Weather:
Snowpack:

Photos:

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Natural avalanche from Almont area – shared via text message to CBAC

CBACCBAC Observations

Date of Observation: 03/11/2023
Name: Text Message Obsevation

Zone: Southeast Mountains
Route Description: This area sits outside the CBAC forecast area just north of Almost above highway 135 (forecaster description)

Observed avalanche activity: Yes
Avalanches: Natural avalanche north of Almont on a northeast-facing slope, around 8,400 feet.
Weather:
Snowpack:

Photos:

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Thick storm snow!

CBACCBAC Observations

Date of Observation: 03/11/2023
Name: Eric Murrow

Zone: Southeast Mountains
Route Description: Lower Anthracite Mesa from Washington Gulch Trailhead.

Observed avalanche activity: Yes
Avalanches: A few natural storm slab avalanches on east and northeast aspects, D1 – D1.5. Intentionally skier triggered a moist Loose avalanche on a southeast slope below treeline.
Weather: Mostly cloudy skies, about 20 inches of storm snow, light to moderate winds, and mild air temps. Just afternoon there was a period of ‘green housing’ from the sun poking through thin clouds that quickly warmed, settled, and wet snow surfaces on the south half of the compass.
Snowpack: While moving through northeast, east, and southeast aspects below treeline we experienced few signs of instability outside of the natural Storm Slabs that ran during a period of intense snowfall earlier in the morning. On east-facing terrain, we produced a few muffled collapses during a period of strong ‘green-housing’ while surfaces were moist (nearly wet). If I skinned above my partner’s skin track, I was able to produce some ski-length cracks above the established skin track. Test results on an east slope produced an ECTP 28 +1 result and ECTN within the storm snow (see photo). While traveling over a southeast slope, the storm snow had settled and moistened/wetted to a dense, manky 10 inches ( see photo).

Photos:

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A few storm slabs from the Southeast Mountains

CBACCBAC Observations

Date of Observation: 03/11/2023
Name: Zach Guy

Zone: Southeast Mountains
Route Description: Whetstone, Gibson Ridge, and Emmons viewed from Mt. CB

Observed avalanche activity: Yes
Avalanches: A handful of D1.5 to D2 storm slabs at all elevations. Had decent visibility and did not see anything that stepped down deeper from Whetstone to Axtell to Emmons.

Photos:

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