Hot White Lava Flow

CB Avalanche Center 2016-17 Observations

Location: Paradise Divide Area
Date of Observation: 03/19/2017
Name: Tim Brown
Subject: Hot White Lava Flow
Aspect: North, North East, East, South East, South, South West, West
Elevation: 9,600′-12,600′

Avalanches: WL-N-D2.5 (from March 18th?) on a steep, cliff-laden SE aspect ~12000′, debris confined by gully, ran ~2,500′, gouged out old snow and produced some small crowns on the sides of the gully. I don’t think this was triggered by cornice fall and although I could not make out a crown from my vantage points, this may have been a wet slab rather than wet loose avalanche.
Weather: Hot and sunny with light westerly winds
Snowpack: The transition to a spring snowpack is well on it’s way, but not yet very dependable. The window of good corn skiing was pretty short-lived on sun-exposed slopes before the crust softened and ski penetration got deep today. Water was running over ice bulges on steep east-facing slopes between 11,500′ and 12,000′ @9:30am. I also noticed a significant crack on a high-elevation SSW-facing slope. I agree that the wet slab concern is growing.

Meanwhile, it’s still dry and “chalky” on high-elevation (>12,000′), shaded northerly slopes.
Stiff, supportable crust lasted until at least 10:30 am on the valley floor of Washington Gulch, but snow in the dense forest barely refroze overnight (moist snow surface at 7:30am @ 10,000′). Stay away clouds!

IMG_1542
IMG_1537
IMG_1491
FullSizeRender-2

Dry snow ATL northerly

CB Avalanche Center 2016-17 Observations

Location: Paradise Divide Area
Date of Observation: 03/18/2017
Name: Evan Ross
Subject: Dry snow ATL northerly
Aspect: North, North East
Elevation: 10,800-12,789

Avalanches: Its finally happened! The Purple Palace Guide Cracks released in some form of wet slab/guide crack collaboration, today.
Weather: Blue bird with a few puffy or high then clouds. Light winds at ridgeline. 2017 Hot. Another bug landed on my goggles at 11,000ft.
Snowpack: Northerly slopes above treeline had a snow surface mix of soft and faceted, to various forms of wind-board or wind sculpted. The combination of these firmer surfaces and the march sun not being high enough yet, are combining to keep the snow surface cool. Tilting more East, from north, the forecasted wet snow travel advice can be followed.

At ridlegline, south slopes where generally firm and supportive before noon. The exception was abnormal shallow slopes that were 50/50 supportive into moist/wet snow below. The next time we were on south slopes proper was around 10,500ft at 2pm and they were generally unsupportive to boots but still supportive to snowmobiles and skis.

Guide Crack release. East Aspect, 10,500ft

IMG_3159

Mt. Crested Butte

CB Avalanche Center 2016-17 Observations

Location: Crested Butte Area
Date of Observation: 03/18/2017
Name: Zach Guy
Subject: Mt. Crested Butte
Aspect: South, South West, West, North West
Elevation: 9,000-10,400 ft

Avalanches: Skied on a few steep southerly aspects mid-afternoon trying to produce signs of instability but got none.
Weather: Hotter than a 2-peckered goat.
Snowpack: Shallow and melting snowpack, generally less than 60 cm below treeline, saw a decent refreeze overnight. Prime corn window on SW’erly aspects was noon, and slopes became unsupportive by 2 p.m. Several hand pits to the ground on S and SW aspects BTL suggest that wet slab concerns are over; the snowpack is homogeneous large weak very wet grains, with drainage well established. It felt like you might be able to trigger a small wet loose in very steep terrain still.
One pit on a NW aspect BTL had moist snow throughout except very wet grains in the top 10 cm, fairly homogeneous snowpack but slightly softer and wetter near the ground.  There were percolation columns piping freewater straight to the ground. There did not appear to be any concerning interfaces/layers for water to pool on in this location, but if there were, free water would have been hitting them.

WNW aspect BTL.  Note the percolation column extending from very wet surface snow strait to the ground.  No problematic interfaces observed throughout the moist snowpack.

BC ski

CB Avalanche Center 2016-17 Observations

Location: Cement Creek Area
Date of Observation: 03/16/2017
Name: El Duderino
Subject: BC ski
Aspect:
Elevation: 8,400 – 10,900

Avalanches: cornice dribble on E slope triggered an impressively wide D2 LW ~40* across from river bend
Weather: Clear sky, light winds at ridgeline @ 12:00 increasing to moderate in the valley floor by 13:00
T: Lo -6C @ TH @ 7:30
0C @ 10,000 @ 11:00
~9:30 On 1st lap noticeably colder as we descended to valley floor
Snowpack: 4-6” re-freeze at all elevations on open slopes.
less so to no refreeze in the dense high N facing pines
appears despite the inversion that radiative & convective cooling did the job on open slopes & the re-freeze was consistent with the previous 2 days in the same zone

Wet obs

CB Avalanche Center 2016-17 Observations

Location: Kebler Pass Area
Date of Observation: 03/17/2017
Name: Zach Guy
Subject: Wet obs
Aspect: East
Elevation: NTL

Avalanches: Evidence of wet loose activity from the past few days on low elevation northerly aspects, in addition to previously observed wet loose on sunnier aspects.
Weather: Few thin clouds. Hot temps; high of 50F at 10,200 ft. Light winds.
Snowpack: Handpit at 10:30 a.m. on an E aspect NTL had very wet grains in to top 20 cm, and moist snow below that There was an ice lens about 30 cm deep from previous pooling water that had refrozen overnight. Dense, wind affected snow at higher elevations appeared to be handling the warm-up better; remained supportive through mid-day except near rock bands, where skis were punching through. Lower elevation trees were unsupportive in the afternoon.

Point release Gibson Ridge

CB Avalanche Center 2016-17 Observations

Location: Crested Butte Area
Date of Observation: 03/16/2017
Name: Charlie T.
Subject: Point release Gibson Ridge
Aspect: East
Elevation: 9000

Avalanches: See photo. Ran between 10:30 and 12:30 today. Point release looks to have been just below the cornice at the top of Gibson Ridge. E aspect at the S end of Gibson Ridge.
Weather: Bluebird
Snowpack:

IMG_1238

Unsupportive snowpack in the afternoon

CB Avalanche Center 2016-17 Observations

Location: Crested Butte Area
Date of Observation: 03/16/2017
Name: Zach Guy
Subject: Unsupportive snowpack in the afternoon
Aspect: East
Elevation: 8,900 ft

Avalanches: Fresh D2 wet loose avalanche ran today off of Gibson Ridge (East aspect BTL) and a handful of D1 to D1.5 wet loose above treeline in the Ruby Range (S, SE aspects) that ran in the past day or two.
Weather: Hot temps, clouds increasing in the afternoon. Calm wind.
Snowpack: At 3 pm, the snowpack was unsupportive; boot pen was knee+ deep. On an east aspect BTL, we found water had moved through the entire snowpack and was pooling along several crust layers 30-50 cm deep but draining deeper into the snowpack.

Gibson Ridge, East, 10,000′
Mineral Point, South-Southeast, 11,700′
Hancock, SE, 11,800′

Round Mountain

CB Avalanche Center 2016-17 Observations

Location: Cement Creek Area
Date of Observation: 03/15/2017
Name: Jeff Banks
Subject: Round Mountain
Aspect: North, North East, East, South East, South, South West, West, North West
Elevation: 8,400 – 10,900

Avalanches:
Weather: Clear sky, calm/light winds at ridgeline @ 9:00 increasing to strong NW by 10:30
T: Lo -6C @ TH @ 6:30
0C @ 9:00 @ 10,900
Snowpack: W @ 10,900 ridgeline popped off a 4- 6” thick (Pencil hard) plywood sized wind slab overlying 10mm facets on a 20* slope wind whale
N 10,000-10,900 alternating pencil hard windslab & cohesion less facet wallowing ~12” deep of impressive grain size.
no other signs of instability, but our timing was early for the corn cycle so wouldn’t have seen anything. A few short wallow sections skiing up SE ~ 10:30 sheltered in open glades.
Snow in general seemed shallow but dense E-S-W

Advancing water front

CB Avalanche Center 2016-17 Observations, Snow Profiles

Location: Crested Butte Area
Date of Observation: 03/15/2017
Name: Zach Guy
Subject: Advancing water front
Aspect: East, South East, South
Elevation: 9000-9500 ft

Avalanches: None
Weather: Clear, calm, hot.
Snowpack: Good 30 to 40 cm refreeze overnight. Snow remained supportive on skis until we finished at 1:30 p.m., but started becoming unsupportive to foot pen around 12:30 p.m. Perfect corn in the morning.
Dug one pit on an E aspect BTL. The water front has advanced about 30 cm (very wet grains), and the problematic facet/crust layer is about 45 cm deep (moist). See photo.

DSCN2510-001

Peeler/Oh be Joyful

CB Avalanche Center 2016-17 Observations

Location: Crested Butte Area
Date of Observation: 03/14/2017
Name: Ian Havlick
Subject: Peeler/Oh be Joyful
Aspect: North, North East, East, South East, South, North West
Elevation: 9,000-12,400

Avalanches: handful of natural D1-1.5 wet loose initiating in steep and extreme terrain on SE-SW facing terrain all elevations in Ruby Range. Other southerly slopes appeared well behaved with little moving snow. DId observe wet slab/mud slide adjectnt to Kebler Pass road this evening (photos)
Weather: Warm, very light westerly winds in afternoon. Clear, with strong radiation. no wind transport observed.
Snowpack: Snow surfaces warmed on all but high northwest-north facing terrain near and above treeline. All other aspects moistened and become wet in afternoon to 20cm deep. Surfaces started to re-freeze 5pm in shade. did not dig for lingering PS structure, but did ski steep northerlies, cautiously. Around 1730 surfaces in shade began to re-freeze, but felt wet grained snow extended 30cm deep, losing cohesion late in day.

D1.5 wet loose Afley lower right corner
Schuykill Peak D1 Wet lOose
Wet slab/mud slide Kebler Pass
IMG_2440