Irwin Tenure

CBAC2014-15 Observations

Recent Observations: (Surface, structure, cracking, collapsing, PWLs, Ski Pen)

Wind stripped snow in higher terrain exposing old tracks on west terrain even in mid to lower westwall. Looked like straight west Winds. Small isolated wind slabs up to 1F hardness. Snow remained dry, no solar radiation.

East: Paperboy Route w/ ski cuts, no explosives. Fresh Wind slabs developed very touchy with ski cut triggering wind slab in Swill & Bender. Swill SS-ASc-R1-D1-I. 100’ wide 10-20” deep, ran 500’ through choke. Candy’s & Sonic also triggered but smaller 6” deep, ran short of Choke. Wind slab less developed past pre-evac.

South: Small 4” windslabs in Sunny Shoulder barely running. Cocktail Bowl Skiing very well!

West: Sunset L&R a little wind effected but good, small windslab from a ski cut on round two. 8-12” deep 30’ wide, ran 40’.

Upper Upper: Isolated windslabs in lower UUWW. Not UUWW proper. Very shallow windslabs 1F pulling out and stubbornly running short distances from airblasts. Significant scouring, probably lost 1-3f feet of snow depth from terrain. Probably one reason for no results, decreasing load!

Kebler Pass Area

CBAC2014-15 Observations

Location: Irwin Cat Ski

GENERAL COMMENTS: Snow began in the early am and by 9:30 snow began in earnest with strong winds near and above treeline, but even still filtering into below treeline areas.  Windslabs were very touchy and growing in size 10”+ in E. Barkmarker by the afternoon.  Poor visibility prevented backcountry obs.  Storm really fired up around 1500, with that classic Irwin NW-flow nukage that was continuing as we left for the day.

East: am: Perfect loading speeds and direction for EBM. Cracks shooting 20-40’. Fresh windslabs 6-10” deep. Remotely triggered Bender from Swill and got Candy’s to clean out wall to wall while approaching the cornice mid day. D-.5 -1.

South: Sunny Shoulder had stout crust (3-5 cm), (Jan 3 interface) with only 1-2” of new snow on top in the am. New snow seems to be bonding OK with minimal sluffing.

West: UWW, Moonrise, Far Out, Sunset, feeling slabby but not yet slabbed up across extensive terrain. Classic 6-10” windslabs on little rolls behind tree islands, but not long running, or widely propagating… yet. Round two Below Moonrise two small pockets 6-8” deep 20’ wide not really running. Did seem that the new wind and snow was touchy in areas holding yesterdays SH/MFcr combo….worth watching.

 

 

Crested Butte Area

CBAC2014-15 Observations

Name: JSJ
DATE: 1/3/15
Location: Guides Ridge Climb
WEATHER: Cold !! Broken to overcast skies throughout the day. Moderate NNW by mid day transporting snow to lee slopes.
SNOWPACK/AVALANCHE OBS: persistent slab problem evident with ski pen around 15-30cm and boot pen to ground over 50% of the time. Windslabs on ridgecrest showed cracking but nothing moving. Rime(ing) found on all surfaces all the way to summit at 12,162′

Kebler Pass Area

CBAC2014-15 Observations

Name: Evan Ross
DATE: 1/3/14
LOCATION:  Evan’s Basin
ELEVATION:  9,500-11,300fr
ASPECT: SE
Weather: Tour between noon and 3pm. Obscured sky and snowing up to S2 at times. Couple inches accumulation at best. Light westerly wind in our area with no drifting snow.

Snowpack: Avoided several steep slopes and a few pillowy looking snow deposits. Other wise no obvious sings to instability. HS was near 70cm down low and up to 120cm at the higher elevations.

 

Crested Butte Area

CBAC2014-15 Observations

Name): Ross
DATE: 1/3/15
LOCATION: Coneys
ELEVATION: 9,400-10,900
ASPECT: E-NE
WEATHER: 9.00am S1 (C), 12.00noon S2 (c) , 3.00 S1 (m) Cold throughout the day. 5c start 15c finish
SNOWPACK/AVALANCHE OBS: Mixed bag out there. New snow sits on surface hoar but accumulations didn’t change things radically. High in Coneys ski cutting produced minor results. Small wind slabs ran 10-20 feet off the cornice convex roll up high, ski pen 20cm,  down low ski pen was 25-30 cm. Amazing how different snow pack was between upper and lower elevations. Many hand sheers produces similar results. Dec 13 interface produced clean to moderate SP results up higher in the bowl, while other tests lower in the bowl resulted in SC collapses at the faceted base. Trap door like down lower. Skied in 1st bowl and skinned up for a second lap in second bowl. No instabilities seen aside from the small wind slab at the top of 1st bowl. The dec 30 release in the pocket of 2nd bowl still obvious.

Kebler Pass Area

CBAC2014-15 Observations

Name: Evan Ross
DATE: 2014-12-31
Location: Scarps Ridge
Elevation 10,000-12,200
Aspect: S-SW

Weather: Clear dog clear! Calm wind at ridgeline becoming light to moderate from the southeast in the afternoon. Some blowing snow at ridelines. The next storm was approaching from the southwest in the afternoon.

Snowpack: Prime time ski time! Great skiing conditions on south facing slopes. NTL and ATL slopes had a dense wind pressed slab from the Solstice storm with fresh low density snow on top from earlier this weak. Didn’t find any signs to instability but managed terrain features and stayed on slopes 35 degrees or less. Surface hoar was widespread in the morning. Vary small, 1-2mm.

Avalanches: Numerous avalanches observed that failed during the Solstice Cycle. Wide propagating slabs on west aspects and smaller pockets on southeast aspects. All startzones likely 35 degrees or steeper.

Crested Butte Area

CBAC2014-15 Observations

Guide(s): Donny (Irwin Guides)
Date: 2014-12-31
Location: Red Lady Glades to Evan’s Basin
Elevation: 9200′ to 12,400′
Aspect: Mostly south

Weather: clear, calm and cold at the trailhead in the morning.  Significant warming during the day.  It was downright pleasant to 11,800′.  Moderate winds from SE on top of Mt. Emmons.  Some blowing snow and loading into Redwell Basin.

Snowpack/Avalanche Obs: Ski pen of 5cm while skinning.  Boot pen varied.  At times it would go to the Dec. 13 interface, other times it would go to the basal facets.  Snow surface was a mix of surface facets and surface hoar.  No signs of instabilities or recent avalanches.  I dug two, quick holes.  The Dec. 13th interface is still there, and the snow above it gains strength the deeper it gets.  Why is it not reactive?  I wonder if the snow since Dec. 13th isn’t starting to facet, maybe some crusts as well, and therefore the change in hardness is less dramatic?  Obviously, I didn’t have time to study in more detail. Thoughts?

Crested Butte Area

CBAC2014-15 Observations

Date: 12/30/14
Location: Red lady glades/evans basin
Elevation: 9,200-11,600
Aspect: S-W

Weather: Overcast/broken S1 at best. Little to no wind. No snow transport.

Snowpack/Avalanche Obs: 5 to 10 cm of new snow, hard to tell in certain areas up high due to wind. Light wind (L) today have filled in rocky areas off the summit and the ridge, not scoured. Thin snowpack up high leading to Evans basin, thin. Foot pen 40cm, ski pen 25cm down lower in the trees. A mix of crust and facets depending on aspect, seems to be bonding well on crust: ski cuts did not produced any results. No activity seen.

Crested Butte Area

CBAC2014-15 Observations

Name:   Evan
DATE: 2014-12-29
LOCATION:  RL glades/Evans Basin
ELEVATION:  9200′ – 11,600′
ASPECT: S – SW
WEATHER: Overcast, flat light, snowing throughout most of the day mostly S-1,  calm wind.
SNOWPACK/AVALANCHE OBS:  Group skiing fun on slopes less then 30 degrees. Ski pin about 15cm or boot top.
Numerous D1-1.5 soft slab avalanches in Evans Basion from the Solstice Storm avalanche cycle. All on high 30 degree terrain facing E-SE. To far away to get more information.