Moist snow and persistent slab

CB Avalanche Center2015-16 Observations

Location: Crested Butte Area
Date of Observation: 04/07/2016
Name: Evan Ross
Subject: Moist snow and persistent slab
Aspect: North East, East, South East
Elevation: 11,200 NTL

Avalanches:
Weather: Clear sky, calm wind, thin clouds starting to build just before sundown.
Snowpack: Quick obs tour in the late afternoon. See media for specifics.

Aspect ENE, Elevation 11,200, Slope 36. Only the upper inch of the snow surface had become moist. The march 6th (lower dusty interface) continues to produce propagating test results on some slopes. ECTP 21 SP with block sliding off. Interface consisted of 4F 2mm rounding faceted particles. The grains themselves didn’t look to concerning, more concerning was the weaker structure surrounded by 1f hard snow.

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Aspect: SE, Elevation 11,200, Slope 25. Moist snow down to an observed depth of 60cm. First ice lens was down about 55cm. Perc columns where above this ice lens but not below. Surprisingly boot pen was only about 10cm 80% of the time.

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Snowboarder triggered slide on park cone

CB Avalanche Center2015-16 Observations

Location: Cement Creek Area
Date of Observation: 04/07/2016
Subject: Snowboarder triggered slide on park cone north chute towards the dam at Taylor Resevoir
Aspect: North
Elevation: 11,900ft

Avalanches: About a 1 foot deep windblown slab broke loose from the top of the chute and traveled around 500 feet down the slope until it slowed down and stopped. It dragged a snowboarder down the slope about 50-60 feet. He managed to stay upright and cut into a safe zone.
Weather: Bluebird day around 10am
Snowpack: A fairly deep layer of powder up top with hard packed crust underneath.

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Corn to slop

CB Avalanche Center2015-16 Observations

Location: Kebler Pass Area
Date of Observation: 04/07/2016
Name: Zach Guy
Subject: Corn to slop
Aspect: East, South, South West, West
Elevation: 10,000-12,000 ft

Avalanches: A couple new D1 wet loose on East face of Mt. Owen ATL today.
Weather: Hot day…Temps reached 50F at 10k and 38F at 12k under calm/light winds and few clouds.
Snowpack: Solid refreeze overnight. Good corn skiing in the morning turned to sloppy mush by the p.m. Top 6″ or so hasn’t quite transitioned to mature wet grains yet; skier triggered a few rollerballs on East NTL around 11 a.m. and skier triggered widespread large rollerballs on West aspects around 2:00 p.m.

Mountain Weather

CB Avalanche CenterWeather

Date: 04/07/2016

Little change in today’s weather compared to yesterday. High temperatures will be a few degrees warmer with generally light winds and clear sky. Unsettled weather will return to the area tomorrow afternoon and extending into next week. Late Friday afternoon we’ll see increasing clouds as moisture begins to surge in from the southwest. Friday night into Saturday we should see some snow accumulation but this unsettled weather isn’t looking to impressive. A low pressure system is forecasted to weaken as it reaches Colorado around Sunday night. This could help to produce better snow numbers by Monday morning but we’ll have to wait for later forecasts to see how that system holds together.

Mountain Weather

CB Avalanche CenterWeather

Date: 04/06/2016

A high amplitude ridge will bring a warming trend and clear skies for the next few days, before a more active weather pattern arrives this weekend. Look for daytime highs and overnight lows to notch up roughly 5 to 8 degrees warmer each day through Thursday.

Mountain Weather

CB Avalanche CenterWeather

Date: 04/05/2016

A low pressure system is descending on Colorado today from the northwest. Mild temperatures, increasing winds, and mostly cloudy skies are on tap today until a weak cold front pushes through this afternoon. We could see a few inches of new snow as this system moves through, followed by high pressure and warming temperatures quickly rebuilding tomorrow.

Mt. Emmons

CB Avalanche Center2015-16 Observations

Location: Crested Butte Area
Date of Observation: 04/04/2016
Name: Zach Guy
Subject: Mt. Emmons
Aspect: North, North East, South East
Elevation: 9,100-12,100 ft

Avalanches: No signs of instability observed except skier triggered pinwheels on ENE aspects NTL and a handful of wet loose that ran sometime in the past three days on various sunbaked slopes, uncertain of their timing.
Weather: Very warm, moderate SW wind, few clouds increased to broken through the day.
Snowpack: Freewater accelerating deeper into the snowpack, with unsupportive wet grains observed on SE NTL and E/ENE BTL this afternoon (Boot pen was knee to waist deep in wet snowpack).
Targeted profiles on suspect persistent slab slopes showed variable results on the March 6th facet layer below a faceting or wetting slab. See photo captions below for profile/test results.

Coon Basin, NE aspect Near treeline. 35 cm, 4F+ slab over thin crust with rounding facets above and below. ECTN17 on 1.5mm rounding facets below the crust.

Coon Basin, NE aspect Near treeline. 35 cm, 4F+ slab over thin crust with rounding facets above and below. ECTN17 on 1.5mm rounding facets below the crust.

Climax Chutes. NNE aspect near treeline. 42 cm, 4F- faceting slab over 1.0 mm, 4F- rounding facets. ECTN 28 on this layer.

Climax Chutes. NNE aspect near treeline. 42 cm, 4F faceting slab over 1.0 mm, 4F- rounding facets. ECTN 28 on this layer.

Crown profile of skier triggered avalanche last week in Climax Chutes. ENE aspect NTL. 38 cm wet (top 15cm) to moist slab over 1.5mm F+, dry rounding facets, capped by a thin crust in places. ECTP19, SC

Crown profile of skier triggered avalanche last week in Climax Chutes. ENE aspect NTL. 38 cm wet (top 15cm) to moist slab over 1.5mm F+, dry rounding facets, capped by a thin crust in places. ECTP19, SC.  Water pooling along upper dust/crust layer, 15 cm deep.

Looking east across the crown of the skier triggered slide in Climax Chutes last week.

Looking east across the crown of the skier triggered slide in Climax Chutes last week.