Location: Crested Butte Area
Date of Observation: 12/22/2018
Name: Zach Kinler

Subject: Interface check-in
Aspect: North, North East
Elevation: 9,200

Avalanches:

None Observed

Weather: Breezy NW winds in the open, snow showers up to S-2 before clearing skies.
Snowpack: Quick tour on lower Gunsight Pass Rd. Two recent interfaces have been buried and smaller storms are starting to build the slab especially North and West of town.

Pictures from this zone show the two layers @11cm and 17 cm from surface and the well-preserved nature of the 12/19 SH still upright and in tact.

Photos:

Location: Kebler Pass Area
Date of Observation: 12/22/2018
Name: Joey Carpenter

Subject: AMR
Aspect: North, North East, East
Elevation: 10200-11400

Avalanches:
Weather: Skies varied between broken and overcast, intermittent snowfall with rates up to S5 and 2-3 inches accumulation throughout the day. Winds averaged in the mid-twenties, gusts in the 30s out of the NW->N and strong snow transport. Cold.
Snowpack: Last nights accumulation 4 inches with 2-3 more throughout the day. Wind was transporting snow into thin, stiff windslabs in some areas we traveled. Soft, small storm slabs (D.5) were reactive in isolated, rolling terrain steeper than 35 degrees.

Photos:

Location: Crested Butte Area
Date of Observation: 12/22/2018
Name: Aaron Peterson

Subject: Weakness under Windslab at Snodgrass test pit
Aspect: North
Elevation: 11,100

Avalanches:

Lots of sluffing in the top 10cm of new snow on the decent. Nothing else noted.

Weather: Overcast, light snow with occasional graupel, low 20s F, strong west winds in the open and at tree-tops but calm in the trees.
Snowpack: Found a prominent wind-loaded feature on 20deg, north-facing terrain near the top of First Bowl on Snodgrass. Likely formed on 12/19.

HS 90cm with 10cm of new snow on top of a 15cm windslab on top of 4F-1F midpack. 15cm of faceted snow still present at ground level.

ECT 21, Q3. Failed on top of the basal facets. Same result on second test. Shovel shear failed at same level with moderate pressure.

Photos:

Location: Paradise Divide Area
Date of Observation: 12/22/2018
Name: Billy Barr

Subject: Gothic 7am Weather Update
Aspect:
Elevation:

Avalanches:
Weather: Light snow after dark but most came a bit before sunrise, letting up when the wind kicked up around 5:30. There has been 3″ new snow and water of 0.20″ with 23½” on the ground. Temperature stays mild with the overnight low 21 and currently 24. Wind became strong near 6 a.m. and is gusting to 25 mph currently and a steady 5-15 W.
Snowpack:

Photos:

Location: Paradise Divide Area
Date of Observation: 12/20/2018
Name: Eric Murrow

Subject: P-Divide sunny alpine
Aspect: South East, South, South West, West
Elevation: 10,800 – 12,450

Avalanches:

One fresh looking avalanche (crown still pretty sharp) on a westerly terrain feature that gets loaded from northerly winds. D1 in size

Weather: Lots of sun with thin high clouds filtering the sunlight. Light winds through late morning and early afternoon; as we left the area around 1pm winds began to blast snow around in the alpine- did not look like much loading just a blustery mess.

Snowpack: On ascent, we crossed a westerly slope near treeline that I had crossed about a week ago and found that it had weakened during this period and didn’t seem to have as much strength – ski pen was deeper than a week earlier. Surface on this west slope was still dry without a sun crust present.

Much of the alpine terrain visible from up high looked scoured and beat up from the previous days wind event.  I bet there were a few small, fresh, thin windslabs out there tucked behind terrain features like the one pictured below. Skied a south facing slope that had 2-4 inches of new snow resting on a semi-supportive crust. Skied through the drifty looking SE facing feature in the area and did not find a windslab. Looks like the wind blew the snow further downslope or into the basin below. At around 11,200 in the basin found a small isolated strip of deposited snow up to about 10″ thick-not avalanche terrain but made for about 10 quality turns.

Photos:

Location: Paradise Divide Area
Date of Observation: 12/20/2018
Name: Evan Ross

Subject: Afternoon Lap. Skook
Aspect: North East
Elevation: 9,000-11,300

Avalanches:
Weather: Clear other than some high thin clouds. Calm wind.
Snowpack: Getting pretty simple out there. Couldn’t find a persistent slab to worry about, and didn’t encounter a wind slab to worry about either in the one line skied. Feeling around on the BTL to NTL skin up, HS increased from about 60cm to 90cm on average. Those numbers are low because just about everything out there in our area had previously avalanched a couple weeks ago. The snowpack is fast and fun on skis, with ski pen around an estimated 20cm. While boot pen is sinking right through most of the pack. Even the trees had wide propagating avalanches from earlier in the winter. The 12/19 interface will be the new layer of concern as we build back the slabs. The NSF at the 12/19 interface is much more pronounced and weaker below 11,100ft, while increasing in elevation above that, the grains start decreasing in size and are not quite as weak. About 2-3″ of new snow on the 12/19 interface overall.

Poked a hole on the edge of some wind-loaded terrain with a great fetch for westerly winds. Wind-loading had come from the west, but also down the ridge from the northwest. Maybe not the best orientation for the biggest wind slabs to develop out or the last 24 hours. Never the less the windslab was only around 4-5″ thick here and tilt test had it fail within the new snow and just above the NSF. This was a P hard slab in the upper 2 inches and 4f below that. HS here was 130cm as it was above the crown from the natural avalanche activity a couple weeks ago. Probing hear had a more pronounced strong over week structure but its total area was very small.

Photos:

Location: Kebler Pass Area
Date of Observation: 12/19/2018
Name: Tyler

Subject: Red Lady Glades
Aspect: South East, South, South West
Elevation: 11,600

Avalanches:

No observed avalanches or signs of instability

Weather: Periods of intense snowfall and windy flurries. Windy in the open and on the ridge, relatively still in the trees. Lots of blowing snow where there was heavy wind. Wind out of the West
Snowpack: Stayed on low angle terrain all day and saw lots of different snowpack make-up. Where areas were highly wind effected and wind scoured there was hardly any new snow where protected areas had large deposits (during one low speed turn I felt new snow reach up to just below my knee while riding above the crust below the new snow). A crust was present beneath the new snow accumulations on most aspects at all elevations. The crust varied in its thickness and strength.

Photos:

Location: Kebler Pass Area
Date of Observation: 12/19/2018
Name: Tom S

Subject: Anthracite Range
Aspect: North, North East, South
Elevation: 10300′ – 11,7500′

Avalanches:

N/O

Weather: The weather Fx was pretty much spot on 4″ of new snow in the Anthracite range. The majority of the snow came early than forecasted with heavier precip. rates between 8 and 10 AM then tappering throughout the rest of the day. The winds were exactly as forecasted steady from the N in the 20mph range and gusting to 40 at noon. Temperatures remained in the teens to twenties throughout the day.
Snowpack: “Little bit of blowing snow.” Windward slopes becoming wind scoured with strong gusts disrupting the surface hoar. Old tracks still visible on all aspects observed there was some small wind slab development on NE aspects but isolated to areas NTL. Not too much wind loading observed on S aspects 3-4 inches of new on top of a 1″ crust. Saw no signs of instability through the day. Dug one PIT N aspect 10,400′ ETCX burping the burping the baby to see the reactivity of the newly buried surface hoar (profile attached). This will be a layer to pay attention to in the future after our last period of high pressure.

Photos: