Location: Kebler Pass Area Date of Observation: 01/04/2017 Name: Steve Banks
Subject: Irwin Tenure Aspect: East, South East, South, South West, West Elevation: 10,400-11,1700
Avalanches: Morning D1 avalanches reliable skier triggered within the storm snow or at the interface of old snow. Minimal propagation, running fast, dry and light. By afternoon aspects from E->W became very touchy with more propagation, stiffer snow and some surprising remote triggers, almost everything steeper than 34° was moving. Still nothing bigger than D1.5 and running within the new snow, but it’s happening…. Weather: OBS all day with heavy snow in the morning (S5) and strong winds in the afternoon. Temps near 20 Snowpack: Snow went upside down quickly. Morning study plot measurements showed 8″ of 3.5% density super fluff. Great skiing. Afternoon measurements showed 6″ additional at 12%. Heavily wind affected. Skiing became very different–stiff and harder to keep the tips up!
Snow will continue today as a very slow moving cold front with associated heavy snow and wind sinks southward into the central Colorado Rockies and stalls over the Elk Mountains. As that cold front moves through, snowfall rates will spike, and visibilities may drop significantly. Behind the front, colder, drier air moves in, shutting off the tropical moisture tap, and leaving gradually clearing skies and frigid air for tomorrow.
Dry weather will be short-lived with another minor disturbance moves into our area Saturday, then more active weather fed by more fish tacos (Baja style) arrives Sunday afternoon as a closed low develops off the Mexican coastline, and ejects into the desert southwest. This system will combine with westerly flow from the Gulf of Alaska for another doozy.
Location: Crested Butte Area Date of Observation: 01/04/2017 Name: Jeff Banks
Subject: town avalanches Aspect: North, North East Elevation: 9,000
Avalanches: nearly all of the bench slope above nordic center and hockey rink ran in 2 separate avalanches.
2 x SS-ASr-R4-D1.5-I/O
the initial failure was ~20cm down from the surface, then stepped down to the storm snow interface on NSF & SH ~40-50cm deep. Some areas of crown were small cornices (1F) buried in der Über fluff. Some slabs failed ~5cm within the NSF. Critical slope angle for release was ~37/38*
I also triggered a D1 and the whole slope fractured and slumped with an
Artificial subaru trigger (ca. 1996, rust colored) as I “rubbed” the snow bank around the lumberyard corner and rubbin’ son is racing.
Lot’s of R4 roof-a-lanches with well aimed single snowball triggers failing within the storm snow leaving ~15cm depth on the roofs. Weather: snowy Snowpack: widespread cracking and propagation going ~100m & triggering avalanches
Location: Crested Butte Area Date of Observation: 01/03/2017 Name: Peter Innes
Subject: Snodgrass Avalanche Aspect: North East Elevation: 10,700′
Avalanches: We skier triggered a soft storm slab down-ridge, just north of Snodgrass summit. I believe people call this 3rd Bowl (or maybe 2nd Bowl)?
Time: 1300
Aspect: NE
Elevation: 10,700′ (BTL)
Slope: Concave like a bowl, ranging from 38 º to 45 º at its steepest. Average angle ~40º
Size: D1.5, ran for ~150′ before losing momentum and stopping in the trees below.
Crown: 10″ deep, 30′ wide and widening to 40-50′ at flanks.
Bed surface: near surface facets
Skier was caught briefly by the slide but was carried only a dozen feet or so and not buried. This slide took us be surprise, although in hindsight it shouldn’t have given the slope angle. We skied slopes BTL up to 35º with no signs of instability; the storm slab seemed incohesive and didn’t produce results in a column test. This was certainly a wake-up call and a free lesson in decision making/terrain management. It would have been easy to stick to Weather: Moderate snow and winds all afternoon, temps hovering around 20 degrees F for most of the day. Skies partially clearing late in the afternoon with snowfall tapering momentarily. Snowpack: Storm totals (since Sunday) are just under 20″ in the Gothic/Snodgrass zone as of Tues night. Storm snow falling mostly on near surface facets on NE aspects but with minimal apparent instability. As noted a day prior, storm snow on S aspects NTL (shoulder of Gothic Mt) was bonding poorly to a significant crust.
Location: Kebler Pass Area Date of Observation: 01/03/2017 Name:
Subject: Anthracite Storm Slabs Aspect: North, North East, South Elevation: 11200-10000
Avalanches: Intentionally triggered multiple small storm slabs. Small r1d1 in rock, from left side convexity. r2d? in Big Chute. Triggered from wind loaded pockets near top on skiers left. Debris did not break small trees but piled deep enough to bury a person in terrain trap on bottom right of big. Released small sympathetic slab on steep roll above terrain trap. Also intentional remote trigger by jumping on convexities: r1d2 on skiers right of south facing bowl across from 7th. Broke 100ft wide, ran to flats. Numerous crowns in East Bowl and Playground area. More prevalent where wind loading had occurred. Slab activity was limited to steeper terrain. 7th skied with no signs of instability. Weather: s1/s2 off and on. Occasional gusts with some wind transport up high. Snowpack: ~18-24″ storm snow depending on loading
Buckle your seat belts. Over the next 30 hours, the Elk Mountains dive straight into the belly of the atmospheric beast. Snowfall started after midnight, and this morning a few stations have already seen 3″/hour rates. A river of Pacific moisture is pouring into Colorado with good dynamic jet support. These two ingredients alone are forecasted to bring 1″/hour rates all day. A few embedded waves will bring stronger pulses at times. We’ll see moderate westerly alpine winds this morning, intensifying through the afternoon ahead of the cold front, reaching strong to extreme speeds by sunset. The cold front begins to sag south overnight, and snowfall rates spike after midnight, reaching 3″/hour just before sunrise. Tomorrow, winds begin to ease and snowfall starts to taper as the system moves east.
Today
High Temperature: 20 Wind Speed: 10-20 a.m. 20-30 p.m., G45 Wind Direction: SW, W Sky Cover: Overcast Snow: 12-15″
Location: Kebler Pass Area Date of Observation: 01/03/2017 Name: Kirk Haskell
Subject: Red Lady Glades Aspect: South East Elevation: 12 something
Avalanches: Small natural above tree line again lookers left going into bowl , hard to tell with visibility whether it was started by cornice drop . Otherwise no signs of instability Weather: Snow on and off with wind gusting to 20mph Snowpack: Fresh 6″ +
On approach Large cornice build up on the ridge of the Bowl ( Lookers left ).
Location: Paradise Divide Area Date of Observation: 01/03/2017 Name: Zach Guy
Subject: Touchy storm slabs and cornices on Schuylkill Aspect: North, North East, East Elevation: 9,000 – 11,400 ft
Avalanches: 2 natural slab avalanches on NE aspects NTL, a D2 and D1.5. From the ridgeline, about 6 soft slab avalanches were skier triggered, ran on the storm interface, 1 to 2 feet thick. Most failed on buried surface hoar, a couple also failed on near surface facets. Two were D2 in size. The largest propagated 600 feet across a slope and down a ridgeline, and ran 800 vertical feet, about 18″ deep. Cornices were also touchy; we easily triggered 3 or 4 from a distance, and it looked like one failed naturally or was triggered by a group in front of us. Skier triggered some minor pockets on steep rollovers below treeline, failing on surface hoar layer 8-10″ deep. Weather: S-1 to S1, about 2″ of accumulation. Moderate SW winds and snow transport, with brief gusts of intense transport. Overcast skies. Snowpack: ~10″ of storm snow below treeline. Storm slabs up to 3 ft thick near treeline, up to 4F in hardness in heavily windloaded features. Observed several shooting cracks an one muffled collapse. Storm interface is either near surface facets or surface hoar, varies from slope to slope.
Skier triggered soft slab, ~600 feet of across and down ridge propagation. Skier top right for scale. SS-AS-R2-D2-I.
SS-AS-R2-D2-I
Touchy cornices. Give em a wide berth.
D1.5 soft slab. NE aspect NTL.
Checking out an 18-24″ crown on a north aspect NTL. Failed on surface hoar.
Natural D1.5 soft slab. NE aspect NTL.
Large cornice fall….looked to be skier triggered by group in front of us.
Buried surface hoar: Culprit weak layer in a lot of the slides observed today.
Minor cracking and small slabs below treeline, on surface hoar
Natural on Climax Chutes, debris hit valley floor. SS-N-R1-D2-I
Natural on Climax Chutes. SS-N-R1-D2-I
Shooting crack. 50 feet long. 2 to 3 feet deep. Not quiet steep enough to slide.
