Elkton Study Plot

CB Avalanche Center 2019-20 Observations

Location: Paradise Divide Area
Date of Observation: 12/04/2019
Name: Zach Kinler

Subject: Elkton Study Plot
Aspect: North East, East, South East, South, South West, West
Elevation: 10,400

Avalanches: No new avalanches observed.

Weather: FEW, Light West winds, Tair @12:40 was +1.0C. Strong solar, very comfortable day!

Snowpack: HS only increased by 3 cm since last Wednesday despite ~25 cm accumulation during the week. This settlement has created a 1F- hard slab sitting on top of the 11/25 Interface which is 2 mm facets capped with a 1 cm faceting crust. This structure, with the stiffer slab, was able to produce easy CT results (CT5 SC Q1) and propagating ECT results (ECTP10).

Moderate CT results (CT 20 RP Q2) and non-propagating ECT results (ECTN12) were observed at the 11/29 interface which consists of 1.5 mm near surface facets.

Good Coverage at Rainbow Lake

CB Avalanche Center 2019-20 Observations

Location: Kebler Pass Area
Date of Observation: 12/01/2019

Subject: Good Coverage at Rainbow Lake
Aspect: South
Elevation: 10,698

Snowpack: above 10,200 the snow starts to stack up… in the sheltered trees BTL the snow and skiing is pretty good. ATL more wind effected as you’d expect.

Red Lady Glades

CB Avalanche Center 2019-20 Observations

Location: Kebler Pass Area
Date of Observation: 12/03/2019
Name: Sam Roberts

Subject: Red Lady Glades
Aspect: East, South East, South
Elevation: 9,000′-11284′

Avalanches: None

Weather: The day started as mostly overcast with a few flakes flying and a slight wind coming in from the west. As we skinned the clouds began to break and the wind remained with the occasional gust up to about 10mph. The decrease of cloud coverage saw an increase in sunlight and the temperature rose quickly from around -5 degrees C to about +1 degrees C by noon.

Snowpack: VERY THIN. Overall the glades are a 100% no-go and I would not recommend them to any friends or family just yet. We went up anyway. The skin track is the usual track but with many more logs and bushes in the way. We skinned until we reached the rim of red lady bowl the went west into the glades for a pit. The pit was just as we expected from the skin up, shallow. Snow totals ranged from 25-45 cm total in a E-SE-S facing gully at 11284′. There were 2 distinct layer, the first being the last storm snow that consisted of rounded grains of fist hardness (with the basal 2-3cm developing into facets) ranging from 20-40cm below a 2-4cm thick sun crust. Above the sun crust was 3-5cm of fresh snow that had been blown in by the wind. No test were conducted, the only reactivity I saw was the 2cm sun crust cracking and sliding on top of the storm snow. This quickly degrading new snow under that sun crust could cause problems whenever this area gets more snow.

The Creek Called Cement

CB Avalanche Center 2019-20 Observations

Location: Cement Creek Area
Date of Observation: 12/03/2019
Name: Zach Kinler & Eric Murrow

Subject: The Creek Called Cement
Aspect: North, North East, East, South East, South, South West, West, North West
Elevation: 9000′ – 11650′

Avalanches:

Snow volumes are greatly reduced in the Cement Creek area even at its head. Only avalanches observed were on Hunter Hill’s leeward side, NE and ENE slopes, above treeline – very drifty.

3xSS-D1-R1-O ATL, NE
1xSS-D1.5-R1-O ATL ENE

1xSS-D1-R1-O ATL E

Weather: The morning began mostly cloudy with mild temperatures. By the afternoon skies were mostly sunny. Winds were very light near treeline from the WNW. A skiff of new snow overnight.
Snowpack: HS ranged from 20 to 50cm throughout the length of Cement Creek. Around 11000′ there was a noticeable uptick in volume. S and SE aspects developed a 2.5cm MFcr up through the highest elevations we traveled, 11650′; the crust was quite soft.

Dug a profile in a northeast-facing drifted feature at 11,500′ and found 74cm or so of snow. Slab development since November 20th was 44cm and up to 4finger hardness. We observed a couple of smaller collapses, up to 30 feet distance. Boot penetration was to ground. Old snow at the ground was 2 to 3mm DH capped by a friable crust. See profile

Easterly facing slopes near treeline had patchy old snow near the ground not creating continuous coverage on a slope scale. We observed a couple of collapses but very localized.

Snow coverage is becoming much more continuous in the shallow Cement Creek drainage. see photos

Very little to no avalanche hazard on sheltered slopes near and below treeline on all aspects as volumes are lean and slabs are thin and very soft. Drifted locations near and above treeline are the terrain locations that hold avalanche concerns; north through east-facing slopes are the bullseye. Strong winds from last weekend appeared to have formed very small, stiff slabs on cross-loaded features on a variety of aspects at upper elevations.

Photos:

Poverty Gulch

CB Avalanche Center 2019-20 Observations

Location: Paradise Divide Area
Date of Observation: 12/01/2019
Name: Evan Ross

Subject: Poverty Gulch
Aspect: South East, South
Elevation: 9,900-11,900

Avalanches: Carnage all over the place from the 11/30 natural avalanche cycle. The total tally of observed avalanches from Eric and I is in his observation here. The only additional notable avalanche was the large natural on the South side of Mineral Point. This avalanche initiated in the upper cliffs as a windslab. when that cascaded into the apron below it further propagated in the South facing bowl. I believe the apron propagated on the 11/25th interface, with around a 50cm crown. This is estimated as I didn’t do a crown investigation.

Weather: Beautiful mostly clear day with a few high clouds. Light winds will a small amount of snow continuing to drift.

Snowpack: A couple collapses where old October snow was lingering as a collapsible crust near the ground. This collapsible crust was isolated in the terrain we traveled. Otherwise managed the terrain with the old wind slabs in mine. The 11/29 and 11/25 interfaces didn’t appear that they will pose a persistent issue, but managing the terrain with the old wind-loading in mind was still great travel advice as these interfaces continue to adjust to the new load.

1st major avalanche cycle of the season

CB Avalanche Center 2019-20 Observations

Location: Kebler Pass Area
Date of Observation: 12/01/2019
Name: Eric Murrow

Subject: 1st major avalanche cycle of the season
Aspect: North, North East, East, South East, South, South West, West, North West
Elevation: 9000′ – 11,650′

Avalanches:

Hot dang, there sure was a natural cycle in the terrain to the northwest of Crested Butte around Saturday 11/30. Heres what was visible from travel through slate river corridor and poverty gulch. Some failed early in storm and refilled while others fail late with sharp crowns.

Climax: 4x-SS-D2.5 NTL NE
Peeler: 1x-SS-D2 NTL E
Redwell: 1x-SS-D2 ATL NE

Schuylkill Ridge:
1xSS-D2-R3-O NTL NE
1xSS-D2-R3-O BTL NE

Schuylkill Peak:
1x-SS-D2.5 NTL NE
1x-SS-D2.5 NTL N (Baxter Basin)

Schuylkill SubPeak:
1xSS-D2 NTL ENE
1xSS-D2.5 NTL N
3xSS-D1.5 NTL NW

Daisy Pass:
1xSS-D2 NTL E
2xSS-D1.5 NTL NE

Mineral Point: SS-D2.5-R2-I ATL S

Angle Pass:
SS-D2.5-R2-O ATL NE
2xSS-D2 ATL NE
1xSS-D1.5 NE

Afley: 1xSS-D2.5 ATL NE

Weather: Cool day with light winds and decent solar. Overall a comfortable day. No transport observed during the day.
Snowpack: Traveled on mainly south and southeast aspects in the poverty gulch area. HS on these aspects was roughly around 50 to 60cm (much of the terrain we moved through was open and susceptible to wind transport so HS across terrain was variable). Much of this terrain was dry prior to Nov 20th storm with only drifted features holding on to old crust or very isolated facet/crust set up. We did experience a couple of collapses but on isolated wind whales. Interfaces from Nov 25th and Nov 29th storm did not appear concerning or produce results in hasty hand tests, no cracking observed. Snowpack on these sunny slopes was surprisingly supportive to skis.

Photos:

Partial burial at anthracites

CB Avalanche Center 2019-20 Observations

Location: Kebler Pass Area
Date of Observation: 12/01/2019
Name: Lee pow

Subject: Partial burial at anthracites
Aspect: North, North East, North West
Elevation:

Avalanches:

Big chute on anthracites. Dropped 3 cornices on big chute from the overhead cornices skiers left at top of run. Most of the gut of the run slid below the first tree band/rollover, 100cm to ground. Proceeded down the run and stopped at first safe zone on skiers right, when I peeled back onto the run, some hangfire caught me and carried me 100 feet, buried to neck. Self rescue.

Dug an ect at the bottom of the run before dropping (thought a lower pit would be more indicative of the line vs digging above)
Lots of spatial variability

Talking to others at the sleds, many cracks were observed everywhere at the cites, but 7th bowl, due to buried weak layer. One crack was reported to move ~4 feet but did not run.

Weather: Clear and cold
Snowpack: About 100cm

Photos: added by CBAC forecast staff on 12/3.  Photos from 12/2 site visit

Whoomphing/collapsing Slate River area

CB Avalanche Center 2019-20 Observations

Location: Paradise Divide Area
Date of Observation: 11/30/2019
Name:

Subject: Whoomphing/collapsing Slate River area
Aspect: North, North East
Elevation: 10,000-11,000 ft

Avalanches: 

None observed, however we did observe several major collapses and some cracking in flat areas as well as some 30 degree test slopes

Weather: Cold, snowing S1/S2, blowing snow, sustained northwesterly winds with elevated gusts

Snowpack: Thin with nearly no structure below treeline, increasing structure and snow height up to 3 ft near and above treeline with some definite evidence of recent slab formation

 

Still Hitting Rocks

CB Avalanche Center 2019-20 Observations

Location: Paradise Divide Area
Date of Observation: 11/30/2019
Name: SydD

Subject: Still Hitting Rocks
Aspect: South West
Elevation: 11500

Avalanches:

N/A

Weather: A beautiful overcast day, light snowfall (s1), and blistering moderate winds from the west/southwest. Snow and winds relaxed early in the afternoon, chilly all-day
Snowpack: Traveled across large wind whales, and while accending witnessed loud whupping and a few shooting cracks while skiing. The storm dropped close to 10″, but still a very shallow snowpack. No avalanches to report.

Photos:

SW Pow

CB Avalanche Center 2019-20 Observations

Location: Paradise Divide Area
Date of Observation: 11/30/2019
Name: Evan Ross

Subject: SW Pow
Aspect: South, South West
Elevation: 11,000-11,500

Weather: I hiked around with 2 base layers, a softshell, a harder shell, and a big puffy with the hood up. Ooo hiked with my goggles on too. That should explain the weather best to us average people. I’m still cold. Maybe I’m just getting soft? Anyway, the down-valley winds were cranking and continuing to drift snow through the day, while the temperatures where cold. The nearby Cinnamon Weather Stations at 12,100ft showed W-NW winds around 30mph and a high temp of 1 degree. Poor vis with obscured to mostly cloudy sky.

Snowpack: Traveled on very specific SW slopes in the 34-37 degree range on average. Line everything up right, and the skiing was great without the avalanche issue on the other side of the compass. Line it up wrong, and the slope could be blown off by the wind, lacking enough snowpack at too low an elevation, or cross-loaded with a 1 to 2ft deep windslab.

Given the variability and the targeted objectives for skiing its hard to generalize a SW aspect at this elevation. Most SW and south slopes around these elevations are holding a thin snowpack without a current avalanche problem. Add in some more specific variables and you could run into a few more issues. The shaded sides of gullies are holding the old weak October snow. The 11/20 crust can be thick and strong on steep slopes, non-existent on lower angled slopes, and of course transitional in between. Next to the wind-slab avalanche problem, this 11/20 crust was the main potential weak-layer to manage. We had plenty of large collapses while traveling from low angled slopes to a steeper slope, or through sparse trees creating a variable snowpack structure.