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.



CB Avalanche Center 2016-17 Observations, Snow Profiles

Location: Crested Butte Area
Date of Observation: 02/24/2017
Name: Steve Banks/Mike Soucy
Subject: Coney’s
Aspect: North East
Elevation: 9,600-10,800

Avalanches: Kicked off a large cornice resulting in a large collapse and widespread cracking but no avalanche release.
Weather: Cold! -8C at 13:00. S1 most of the day with periods of S2. Light NW/down valley winds. Little bits of broken sky but mostly OVC/OBS all day. Minimal snow transport observed
Snowpack: Very shallow, D1 fresh looking windslab failures noticed above Long Lake below large cornice 2-12” of storm snow. Blown out areas has an inch or two over crust, steeper slopes at higher elevation had good boot top snow. Very wind dependent. Not very slabby and no collapsing or cracking noted. Better skiing where the aspect was a bit more North and has less crust. Snow depths of 190-240 cms with deeper measurements at higher elevations. CTM 15 SP down 24cms below crust failing on grauple below the crust on NE slope 24° Buried SH found 105 down near the ridgtop, but looked flattened and rounded and unreactive.


Schuykill Peak/Pittsburg/Baldy

CB Avalanche Center 2016-17 Observations, Snow Profiles

Location: Paradise Divide Area
Date of Observation: 02/05/2017
Name: Ian Havlick
Subject: Schuykill Peak/Pittsburg/Baldy
Aspect: North, North East, East, South, South West
Elevation: 9000-11700

Avalanches: No new avalanches, but obvious signs of <10″ diameter trees broken, and/or blown over 45º angles by a large avalanche off ESE face of Schuykill Peak this winter.  Impressive.  Also possible evidence of new/extpanded path in Democrat Basin this winter, (fallen/broken trees almost buried).
Weather: Mostly clear, increasing WSW winds throughout day, light to strong especially near and above treeline. Temperatures remained mid 20s at ridgetop, balmy close to 30ºF in valley bottom. Strong solar radiation.

Decent wind transport, loading east facing slopes near and above treeline with <10″ windslabs, bonding well, no cracking, sluffing or signs of instability in new wind drifted snow or old snow.  Did observe spotty surface hoar at ridgetop, but wind was beginning to destroy.  Southerlies the SH was destroyed by radiation and wind.

Dug every 200 vertical feet or so on steeper (33-40º) NE facing slopes to get a sense for 1/19 surface hoar distribution. All profiles near and below treeline revealed concerning structure and slab behavior in long column tests. Consistent ECTP16-21 SP results and PST<30/100end 20170119 on 8-10mm standing, preserved surface hoar, 50-60cm deep, holding a F-1F slab above. Purposely dug on steeper convex rolls to examine structure if flushed previously, or not, and on all slope I dug, SH was still alive and well. Awaiting the big Mon-Weds storm (1-3″ SWE). This incoming rapid load is concerning, and the 1/19 surface hoar should NOT be written off yet, and still well within skier or sled triggerable range.  

Snowmobiled on southwestern facing slopes later in afternoon on south shoulder of Mount Baldy. Yesterday’s storm still generally soft and powdery at higher elevations, steep southerlies got moist and should be monitored for crust/facet combination below tomorrow’s storm.


Cement Creek

CB Avalanche Center 2016-17 Observations, Snow Profiles

Location: Cement Creek Area
Date of Observation: 01/13/2017
Name: Ian Havlick/Evan Ross
Subject: Cement Creek
Aspect: North, West, North West
Elevation: 9000-10500

Avalanches: no new avalanches observed, looked hard, did see evidence of several S-SE facing slopes and gullies. Faint crowns and buried debris. looks like these slides slid early this week.

Big paths on Italian, Cement, etc were difficult to see due to lingering fog/clouds, but no obvious crowns.
Weather: Overcast but gradually clearing most the afternoon, with one light snow shower toward sunset. Calm winds. Temps in mid 20s.
Snowpack: Quite impressive. snowpack averages 150-200cm. Generally solid, rightside up. Dug one profile on W facing slope at 10,300 (BTL). Revealed solid structure with old snow/New Years storm interface gaining strength. ECT produced no results, and slab finally failed cleanly, but stubbornly on aggressive shovel shear after ECT test.

No signs of instabilities in terrain travelled.


Red Mountain

CB Avalanche Center 2016-17 Observations, Snow Profiles

Location: Crested Butte Area
Date of Observation: 01/13/2017
Name: Ian Havlick
Subject: Red Mountain
Aspect: North, West, North West
Elevation: 9200-9600

Avalanches: no signs of obvious crowns on SE facing shoulder of Whetstone or surrounding terrain. Visibility was improving but still limited.
Weather: Overcast skies, snow flurries, temps in mid 20s. light but sneaky south winds.
Snowpack:  40cm boot pen. Steady southerly wind re-filled skin track in 30min.  Found spooky structure digging in a targeted shallow area due to wind scouring/loading/scouring near ridgetop on a NNW aspect.  Profile revealed preserved buried surface hoar from New Years Day, as well as reactive basal facets.  No signs of instability or evidence of recent avalanches on S-SE shoulder of Whetstone, but visibility remained limited during tour.

ECTP24 SP on surface hoar, as well as PST37/100end on SH.

PST20/100 end on basal facets.

surface hoar found 60cm from ground
3-4mm facets from near ground

Italian Mountain Ridgeline

CB Avalanche Center 2016-17 Observations, Snow Profiles

Location: Cement Creek Area
Date of Observation: 12/24/2016
Name: Ian Havlick
Subject: Italian Mountain Ridgeline
Aspect: North, South West, West, North West
Elevation: 9000-12200

Avalanches: Did not observe any fresh avalanche activity in Cement, Spring Creek, or visible surrounding peaks.
Weather: Beautiful sun, intense solar, temps 18-25ºF. SW winds increased to strong early afternoon, died a bit, but increasing again around 1600.
Snowpack: Much different story between below treeline and above TL. Relatively deep (100cm) snowpack near and below treeline, but with ascent into more wind prone areas, snow cover became much more variable and weak. A few booming collapses on 20º, SW facing slope ~11800ft.

Profile BTL, west facing did not produce any results for propagation (PST60/100end, basal facets, ECTX), but profile above treeline, SW facing slope held 1F slab over 4mm depth hoar, ECTP12 SC. Significant wind transport and sensitive windslabs up to 12″ deep forming on NE-E facing slopes and ridgelines.

**One concern for future is widespread 4-5mm surface hoar which developed overnight above delicate suncrust/temperature crust on E-S-W facing slopes. Was destroyed by sun and SW winds on southerly slopes, but east and west facing slopes should be monitored…Could be referred to as XMAS surface hoar event.


Teocalli/W. Brush Creek

CB Avalanche Center 2016-17 Observations, Snow Profiles

Location: Brush Creek Area
Date of Observation: 12/23/2016
Name: ian havlick
Subject: Teocalli/W. Brush Creek
Aspect: South East, South, South West
Elevation: 9000-11500

Avalanches: No signs of instability but did see widespread evidence of 12/17 storm and large avalanche cycle on all N-E facing terrain at all elevations.

Only moving snow today was D1 wet loose sluffing in extreme terrain, and D1 windslabs which looked fresh from this morning’s winds right at ridgeline.
Weather: Partly cloudy, very warm air temperatures and intense solar radiation. Moderate winds at ridgetop in the morning, then calming throughout day.
Snowpack: Generally stable, felt like moderate in terrain travelled today. HS averages ~90-110cm throughout terrain travelled. Top 10cm of surface snow became very moist with greenhousing type scuddy clouds scraping ridgetops, calm winds, strong solar radiation, and near freezing ambient air temperatures. Very small facets already forming under this crust, and the other crust buried 12/22 by last nights snow., down 30cm from surface.  In every pit dug, 2-3mm facets near the ground were found, but no ECTs produced propagation near and below treeline.


CBAC Snodgrass Study Plot Snowpit

CB Avalanche Center 2016-17 Observations, Snow Profiles

Location: Crested Butte Area
Date of Observation: 12/22/2016
Name: Arden Feldman
Subject: CBAC Snodgrass Study Plot Snowpit
Aspect: North East
Elevation: 9760

Avalanches: none
Weather: see profile
Snowpack: see profile