No sings of instability. Large Surface Hoar growth.

CB Avalanche Center2016-17 Observations

Location: Crested Butte Area
Date of Observation: 02/05/2017
Name: JSJ
Subject:
Aspect: South East, South, South West
Elevation: 9,100-12,400

Avalanches:
Weather: Clear and cold at TH…5F @ 8am. Light winds from the NNW w/ Mod gusts at ridge top. Strong solar
Snowpack: No sings of instability. Large Surface Hoar growth found all the way to Mt. Emmons summit at 12,400’ where protected from wind. Strong solar today warming wind sheltered snow surfaces by 1200. Yesterday’s 10-15cms HST bonded well to underlying windboard and suncrusts.

Here we go again

CB Avalanche Center2016-17 Observations

Location: Cement Creek Area
Date of Observation: 02/05/2017
Name: ADB
Subject: Here we go again
Aspect: North, North East
Elevation: BTL

Avalanches: None. Just some rollers off skin tracks.
Weather: Blue bird: calm and clear even on ridgetop
Snowpack: Fields of surface hoar forming in lodgepole up to ridgeline. About 1cm in height.

On portions of skin track punched down to last layer of buried surface hoar. Ski pen: 18 inches.

Avalanche Level 1

CB Avalanche Center2016-17 Observations

Location: Crested Butte Area
Date of Observation: 02/05/2017
Name: Evan Ross
Subject: Avalanche Level 1
Aspect: North East
Elevation: 9,400-11,000

Avalanches:
Weather: Mostly clear sky, calm wind. Warm feel in the sun, but not quite as warm as expected.
Snowpack: SH on the surface in meadows. Burned off on steep southerly slopes. Didn’t observe SH on northeasterly slopes.

No signs of instability. Previous tracks in the terrain on plenty of steep slopes with no results. Skied near a couple week old crown in 3rd bowl. 1/19 SH had been cleared out where this previous avalanche had run, but was still preserved in avalanche terrain on the portions of the slope that hadn’t previously avalanched. 1/19 SH was down about 25cm under a soft slab. These slabs would budge in hand pits or where the slope was cut up between ski tracks. Still no avalanche results in the bigger picture.

1/19 SH down 25cm on the parts of the slope that hadn’t avalanched.

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Schuykill Peak/Pittsburg/Baldy

CB Avalanche Center2016-17 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.
Snowpack:

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.

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Snodgrass Area

CB Avalanche Center2016-17 Observations

Location: Crested Butte Area
Date of Observation: 02/05/2017
Name: Chris Pruden
Subject: Snodgrass Area
Aspect: North East
Elevation: 9000-9600

Avalanches:
Weather: Partly cloudy sky in the afternoon. Winds light and variable where we were but really ripping at ridge top (from the west). Blowing snow observed on Gothic and White. Temps hovered around freezing.
Snowpack: No obvious signs of instability besides a weak structure found during snowpack tests and some small wet loose events on solar aspects. CTM SC and ECTP. The pit was at 9500 with a NE aspect and 25 degree slope angle. Both of these failures occurred 30 cm down on some degrading buried SH. As we were digging we watched some D1 wet loose avalanches coming down on the sunny side of the valley at our same elevation.

Smith Hill

CB Avalanche Center2016-17 Observations

Location: Crested Butte Area
Date of Observation: 02/04/2017
Name: Will Nunez
Subject: Smith Hill
Aspect: North, South West
Elevation: 9,000-9,500

Avalanches:
Weather: Partly cloudy in the morning and broken sky’s in the afternoon. Strong increasing solar/greenhouse affect on the more southerly slopes. Clam to increasing light winds out of the SW.
Snowpack: No sings of instability. HS 180cm 2″ new snow, surface rimed dendrites. CTN on a 27* Slope SW with lots of resistance on the crust facet interface was rounding 35cm down.
Gibson Ridge Obs: No signs of instability. HS 183cm. 4″ new snow, surface Rimed dendrites. Compression Test resulted in CT11SP 140cm 30* N on the mid January buried surface hoar storm interface. See Photos.

Gibson Ridge CT11SP 9,400ft North

will

Avalanche Level 1

CB Avalanche Center2016-17 Observations

Location: Crested Butte Area
Date of Observation: 02/04/2017
Name: Evan Ross
Subject: Avalanche Level 1
Aspect: East
Elevation: 9,000-9,800

Avalanches:
Weather: Partly cloudy sky in the afternoon. Temps and sun combined to warm snow surfaces. No wind.
Snowpack: No sings of instability and no current problems in the snowpack structure. HS about 150cm. 2-3″ new snow that was warmed and schmooooy on top of a soft crust. Would love to add more details but nothing significant enough to note. Would have had to find a very isoated crosloaded feature to maybe see some form of potential avalanche structure on slopes traveled.

No signs or Instability

CB Avalanche Center2016-17 Observations

Location: Crested Butte Area
Date of Observation: 02/04/2017
Name: JSJ
Subject: No signs or Instability
Aspect: North, North East
Elevation: 9,300-10,800′

Avalanches:
Weather: Clearing skies throughout the day, with S1-S2 snowfall in am. Light – Mod NNW winds drifting new snow. Skies mostly cleared by 1400.
Snowpack: No sings of instability. 5cms new snow at TH and 15cm new snow at ridgetop. The new snow was Mostly graupel and stellars that was being drifted at ridgetop into a ‘thick’ feeling wind / storm slab, but warm temps seemed to help it bond to underlying roughened up old hard surface snow.

Variable weather

CB Avalanche Center2016-17 Observations

Location: Cement Creek Area
Date of Observation: 02/04/2017
Name: ADB
Subject: Variable weather
Aspect: South, South West
Elevation: BTL

Avalanches: None. Some rollers below skin track.
Weather: You name it, we had it:
For the most part, skies were mostly broken with light winds. Had some periods of overcast skies and moderate winds as evidenced by skin track being filled in after first lap.
Snowpack: About 3 inches of wet /moist snow over the past 24 hours with 4 inches in a saddle. New snow overlies a slushy layer that was a breakable crust on Thursday.

Snow glopped to skins.

SW side of Snodgrass

CB Avalanche Center2016-17 Observations

Location: Crested Butte Area
Date of Observation: 02/03/2017
Name: Tim Brown
Subject: SW side of Snodgrass
Aspect: South West
Elevation: 9,600-10,800

Avalanches:

Weather: Broken skies with high thin clouds, calm and warm (air temps near freezing)

Snowpack: No signs of instability. Breakable crust (~5cm thick) covers all sun-exposed slopes. HS ranged from 1.5-2.5m with evidence of previous cross-loading. Probing revealed a fairly uniform snowpack except for a few buried crusts.