Mountain Weather 3/12/2017

CB Avalanche CenterWeather

Date: 03/12/2017

Don’t worry spring breakers, Crested Butte beach weather is only temporarily on hold and will return on Monday. A fast moving short wave trough will impact northern Colorado today, bringing light snow accumulations. Here in the center mountains, we’ll just see increased clouds and elevated gusty winds with a very light snow shower at best. This shortwave begins to move on Monday night as the high-pressure ridge over the western US takes hold again. This ridge will bring dry weather with potently record breaking high temperatures into the midweek.

Shallow wet loose

CB Avalanche Center2016-17 Observations

Location: Crested Butte Area
Date of Observation: 03/11/2017
Name: Zach Guy
Subject: Shallow wet loose
Aspect: West, North West
Elevation: 9,000-12,000 ft

Avalanches: A few natural and skier triggered shallow wet loose in the afternoon on very steep, sunbaked slopes.
Weather: Calm to light winds, few clouds, warm.
Snowpack: 3-6″ of wet grains over a solid crust, or moistening dry snow on more northerly tilts.

PS structure near ridgeline

CB Avalanche Center2016-17 Observations

Location: Crested Butte Area
Date of Observation: 03/11/2017
Name: Evan Ross
Subject: PS structure near ridgeline
Aspect: North East
Elevation: 9,000 – 11,300

Avalanches:
Weather: Hot baby hot. With calm winds and few clouds.
Snowpack: Not much for any signs of last weeks epic wind storm in Climax area. PS structure at ridegline on a previously wind-loaded terrain feature. CT24 SP down 45cms on old faceted snow with a decomposing slab on top, but still 1f above the week layer. We avoided this terrain feature. Below ridgeline the slab became thiner and more decomposed as the PS structure tapered away.

On a more easterly tilted, steep slope, small loose wet avalanches were easy to trigger. Observed at 9,600ft. Northeasterly facing slopes were still dry at noon.

IMG_3079

Mountain Weather

CB Avalanche CenterWeather

Date: 03/11/2017

A pair of fast-moving disturbances will brush across the Elk Mountains, keeping unsettled weather through the weekend but with minimal snow accumulations. This first shortwave is bringing cloudy weather and no precip this morning, but we should see skies starting to clear up by this afternoon. Tomorrow’s system will bring stronger winds and spit a few snow showers if we’re lucky. High pressure begins to redevelop into next week, bringing warming temperatures and clear skies.

Irwin Terrain

CB Avalanche Center2016-17 Observations

Location: Kebler Pass Area
Date of Observation: 03/10/2017
Name: Zach Guy
Subject: Irwin Terrain
Aspect: South East, South, South West
Elevation:

Avalanches: None.
Weather: Thin clouds increased through the day. High of 45/24. SW winds 20-25mph, gusting to 45.
Snowpack: Upper 5-10 cm became wet at lower elevations by PM. Began to refreeze around 3p.m.

Mountain Weather 3/10/2017

CB Avalanche CenterWeather

Date: 03/10/2017

Another very warm day on tap, though we will see high clouds spanning across our forecast area. These clouds will help trap daytime heating and contribute to even warmer temperatures than yesterday. West southwest winds will remain generally light at ridge top, with a few moderate gusts ahead of a fast moving disturbance cutting across our area tonight. Clouds will increase toward the afternoon and evening, with a quick 1-4” of snowfall possible overnight. As system moves out tomorrow, sunny skies will return.

Mountain Weather 3/10/2017

CB Avalanche CenterWeather

Date: 03/10/2017

Another very warm day on tap, though we will see high clouds spanning across our forecast area. These clouds will help trap daytime heating and contribute to even warmer temperatures than yesterday. West southwest winds will remain generally light at ridge top, with a few moderate gusts ahead of a fast moving disturbance cutting across our area tonight. Clouds will increase toward the afternoon and evening, with a quick 1-4” of snowfall possible overnight. As system moves out tomorrow, sunny skies will return.

Mount Emmons

CB Avalanche Center2016-17 Observations

Location: Crested Butte Area
Date of Observation: 03/09/2017
Name: Will Nunez
Subject: Mount Emmons
Aspect: North, North East, East
Elevation: 9000-11300

Avalanches: large cornice fall NE aspect, Mid size wet/dry loose slides on southerly’s aspects all in Redwell Basin
Weather: Clear with hint of hays from the west (dust), hot in the lower to mid elevations with, increasing moderate winds with strong gusts out for the NW.
Snowpack: The wind has affected most slopes W-NW-E NTL and ATL with wind board, textured and sustrugi snow surfaces. NE facing slope at 10,500ft HS 190cm with F hardness 30-40cm down to a faceted interface 4F to 1F blow. It looked as though the weak persisting slab structure has faceted out. Strong solar on S-SE slopes had produced roller balls from hot temp the day prier. No other instabilities with observed.

Scarp to Peeler

CB Avalanche Center2016-17 Observations

Location: Crested Butte Area
Date of Observation: 03/09/2017
Name: Ian Havlick
Subject: Scarp to Peeler
Aspect: North, North East, East, South East, South
Elevation: 10,000-12,000

Avalanches: numerous D1 wet loose on SE-S-SW facing slopes.
Weather: clear, 20mph westerly breeze at ridgetop kept ambient temp feeling cold, but strong solar and temps softened all but due north
Snowpack: Did not dig, but all but northerly snow surfaces became moist with temperatures and solar. Snow grains are transforming to granular corn where previous winds last week kept new snow from acccumulating. New snow still has a few more days of freeze/thaw before proper corn develops on e-S-W facing terrain. On shady northerly slopes, surface snow has faceted 20-40cm but underlying snow reamins slabby above facets.

East Beckwith

CB Avalanche Center2016-17 Observations

Location: Kebler Pass Area
Date of Observation: 03/09/2017
Name: Zach Guy
Subject: East Beckwith
Aspect: North East, East, South East, South
Elevation: 10,000-12,350 ft.

Avalanches: Observed about 20 skier triggered and natural wet loose avalanches, mostly D1 to D1.5 in size, although a couple were large enough to bury someone. These were primarily on steep and windsheltered E to SE to S aspects NTL. It seems higher elevations got so blasted by winds that the surface was too dense or crusted for wet concerns under today’s weather. See photos.
Weather: Warm, few/scattered thin clouds. Light winds.
Snowpack: On SE to S aspects NTL, there was 3″ to 10″ of very wet to slushy snow over a firm frozen crust, sliding easily steep slopes.
A pit on a NE aspect NTL showed a mix of hard propagating and non-propagating results on facets below a crust about a foot deep. (ECTP22, ECTN x 3, PST 80/100 END). Above treeline, it looked like a number of suspect northeasterly slopes saw some amount of persistent slab scouring during the recent extreme wind event.

Skier triggered “slub” in action.

D1.5’s. SE aspect NTL

D2 SE aspect NTL.

S aspect NTL. Slow moving skier triggered wet loose avalanches, D1.5. Some failed with a little slab-like propagation.

NE aspect ATL. Old persistent slab crown visible in the shadows. Note the slab erosion textures across much of the face.

D1.5 SE aspect NTL

Mix of non and propagating results on buried faceted crust 30 cm deep. PST 80/100 END shown here.

D1.5, S aspect NTL.