Mountain Weather 12/15/2016

CB Avalanche CenterWeather

Date: 12/15/2016

We will see a short gasp of dry air this morning before unseasonably warm, southwesterly flow ushers in the main event. Temperatures at 5am are already in the upper 20s, and look to approach the upper 30s today. Heavy snowfall will start very warm, even potentially as R A I N below 10,000ft (we’re talking Crested Butte), before a sharp cold front acts as gas on the moist atmospheric fire and cranks the snow tomorrow before clearing out Saturday morning. Precipitation models are getting excited about this recipe, and while they may be going a bit heavy on the pinks and purples, 1-2 feet of snow look likely, with the potential for some impressive totals in the usual places (Schofield and Kebler Passes) by midday Saturday.

Today

High Temperature: 38
Wind Speed: 10-25
Wind Direction: SW
Sky Cover: Mostly Cloudy
Snow: 0-1″

Tonight

Low Temperature: 26
Wind Speed: 15-30 G 50
Wind Direction: SW, W
Sky Cover: Mostly Cloudy
Snow: 4-8″

Tomorrow

High Temperature: 33
Wind Speed: 15-25
Wind Direction: W
Sky Cover: Mostly Cloudy
Snow: 12-15″

Red lady glades

CB Avalanche Center2016-17 Observations

Location: Kebler Pass Area
Date of Observation: 12/13/2016
Name:
Subject: Red lady glades
Aspect: South
Elevation: 11,000

Avalanches: none observed
Weather: Overcast and warm. Windy conditions even below treeline
Snowpack: 58 cm right below treeline. Layered snowpack although relatively consolidated. I saw no signs of instability but there was snow being blown around even in the Aspen trees so I imagine there was a lot of transport up high. Thicker denser snow on the surface from temp and sun but low angle slopes helped to not allow the sunburst to develop.

Mountain Weather

CB Avalanche CenterWeather

Date: 12/14/2016

A skiff of snow fell overnight. A stationary front is parked just north of our forecast area, inhibiting favorable dynamics for snowfall. As moisture deepens through the day under west-southwest flow, we should see a couple inches of accumulation, favoring the Elk Divide to the northeast of town. Gusty alpine winds will accompany any new snow. Get excited for a powdery weekend ahead. A trough tapping into warm Pacific moisture approaches the Elks on Thursday. The first phase of the storm on Friday will be unusually warm, with the rain/snow line creeping near or above our valley floor. A strong cold front boosts dynamics and brings better snowfall production to all elevations on Friday night. Upwards of two feet of snow could accumulate by Saturday.

Today

High Temperature: 28
Wind Speed: 12-22, G40
Wind Direction: SW, W
Sky Cover: Overcast
Snow: 1-3″

Tonight

Low Temperature: 22
Wind Speed: 10-20 G40
Wind Direction: SW, W
Sky Cover: Overcast
Snow: 0-2″

Tomorrow

High Temperature: 32
Wind Speed: 5-15
Wind Direction: SW, W
Sky Cover: Mostly Cloudy
Snow: 0

Mt. Axtell

CB Avalanche Center2016-17 Observations

Location: Crested Butte Area
Date of Observation: 12/13/2016
Name: Zach Guy
Subject: Mt. Axtell
Aspect: North East, South, South West
Elevation: 9,600 -12,000 ft

Avalanches: No recent avalanches observed across all bowls of Mt. Axtell or on northerly aspects of Carbon
Weather: Overcast, light to moderate westerly winds at ridgetop, with minimal snow transport observed.
Snowpack: See photo captions for detailed pit descriptions.
On NE aspects N/ATL. Extended column tests showed propagating results on basal facets/depth hoar, up to a meter deep. Non-propagating results on Dec 6th near surface facet layer, buried mid-pack. We triggered two large collapses on low angle slopes. We did not venture onto any steep terrain at these elevations.
On S/SW aspects N/BTL. The Dec 6th crust/facet layer produced about 5 rolling collapses up to 50+ feet long, but is buried only 6-12″ right now; not much of a slab. Propagating results.
On N/NE aspects BTL, the snowpack felt fairly uniform and soft, becoming progressively weaker with depth but with no distinct or sudden hardness changes. We traveled on several slopes steeper than 35 degrees with no signs of instability.

NE aspect ATL.  3-5 mm depth hoar grains at the bottom of the snowpack.  Difficult to say how continuous this relatively thin layer is across steep slopes due to surface roughness and variability.
NE aspect ATL. ECTX result, but sudden collapse, propagating result with 2 additional hits (ECTP32) on 3-5 mm, fist hard depth hoar, below a ~90 cm, 4F to 1F slab.  Non propagating results on Dec 6th near surface facet layer, about 35 cm deep.
SSW aspect NTL.  ECTP 15, SC below the Dec 6th crust layer (1F, 1 cm thick), over F facets.  30 cm of F to 4F slab above this layer. Rolling collapses observed on this layer, although slab generally felt lacking in these wind protected slopes.
NE aspect NTL.  ECTP 16, SC on 1-2 mm basal facets below a 75 cm slab (F to 4F).  ECTN results on the Dec 6th near surface facet layer (F+) buried about 35 cm deep.

Mountain Weather

CB Avalanche CenterWeather

Date: 12/13/2016

Colorado remains in strong, westerly flow through most of the work week. Radar shows a lull in precipitation upstream of us in Utah and the next pulse of moisture moving onshore over California. Today, we’ll see mid to high level clouds and continued alpine winds with a few snow showers developing tonight. Deepening moisture will fuel a stronger pulse of snowfall tomorrow afternoon accompanied by strengthening winds. A large, closed low is lined up to deliver significant snowfall beginning Thursday night. Stay tuned.

Today

High Temperature: 20
Wind Speed: 10-20, G35
Wind Direction: W
Sky Cover: Mostly cloudy
Snow: 0

Tonight

Low Temperature: 15
Wind Speed: 10-20
Wind Direction: W
Sky Cover: Overcast
Snow: 1-3″

Tomorrow

High Temperature: 25
Wind Speed: 12-22
Wind Direction: SW, W
Sky Cover: Overcast
Snow: 1-4″

Unhappy structure in Happy Chutes

CB Avalanche Center2016-17 Observations

Location: Crested Butte Area
Date of Observation: 12/12/2016
Name: Zach Guy
Subject: Unhappy structure in Happy Chutes
Aspect: North East
Elevation: 9000-9400 ft

Avalanches: We descended slopes up to ~38 degrees with no avalanche activity.
Weather: Broken skies, calm winds, no precip.
Snowpack: Hollow snowpack structure produced widespread cracking ~5 to 15 feet and localized collapsing. 12″, semi-supportive (on skis) soft slab over fist hard facets, consistent structure across all terrain that we traveled. Propagating results in ECT and PST. Small storm slab management still seems to apply here, and it felt like the slab is a little too soft/thin for avalanching or propagating on most features, except for very steep, unsupported, or wind stiffened slopes. Not much additional load needed here for widespread persistent slab issues.

12_12_16-Happy-Chutes-Pit-Profile
DSCN1180-001
wow, we have bright orange hats. And cracking snow.
Lots of localized collapses and cracks.

BC Ski

CB Avalanche Center2016-17 Observations

Location: Paradise Divide Area
Date of Observation: 12/12/2016
Name: Jeff
Subject: BC Ski
Aspect: East, South, West
Elevation: 9800-11400

Avalanches:
Weather: OVC, NW M>S as day progressed
Snowpack: ATL & BTL E-S-W No signs of instability, sleds roosting 35-40* & leaving troughs on the above mentioned terrain with no results. stomped on ridgelines of steep windloaded slopes (HS 80-110cm) no results

intensifying snow transport ~15:00, some quickly blown in tracks @ all elevations in open clearings