THIS AVALANCHE ADVISORY EXPIRED ON March 28, 2017 @ 5:33 am
Avalanche Advisory published on March 27, 2017 @ 5:33 am
Issued by Graham Turnage - Taos Avalanche Center

2. Moderate

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Above Treeline

2. Moderate

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Near Treeline

1. Low

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Below Treeline

MODERATE avalanche danger exists above and near treeline while areas below treeline have a LOW danger today.  Recent snow and moderate WSW winds continue to build isolated wind slabs and human triggered avalanches are possible.  A deeper perisistent slab problem still exists on some slopes.  Evaluate the snowpack and terrain carefully, and be concious of  snowpack variations from slope to slope.

  • Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
Avalanche Problem 1: Wind Slab
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Swirling mountain winds during and after Thursday night's impressive storm have formed wind slabs near and above treeline.  Sunday's fresh snow (5-7") has been effected by the wind and has formed soft wind slabs on the leeward sides of ridges and gullies. These slabs are gaining strength with cold temps and time, but triggering them is still possible, and could result in large, dangerous avalanches on isolated slopes.  These slabs are generally easy to identify and avoid and do not exist on all slopes.

Avalanche Problem 2: Persistent Slab
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Last weeks warm temps and intense sun warmed the snowpack on most slopes, creating a layer of weak, wet snow beneath a thin crust, now buried by 2 feet of new snow.  This layer does not exist on all slopes, requiring careful inspection of the snowpack on the slopes you wish to play on.  Time and colder temps are helping to heal this problematic layer, thus lessening the chances of triggering a persistent slab.  That said, it is still possible to trigger a slide on this layer and a smaller surface avalanche may be enough of a trigger to step down into this old layer of rotten snow.  Areas where the snowpack is thin like rocky ribs have wet facets on the ground which are still willing to propagate in stability tests.

advisory discussion

Friday's spring storm left us with 2 feet of snow and about 2.5" of Snow Water Equvialent (SWE) followed by 5-7 inches of snow in most mountain locations in the early morning hours on Sunday. This winter weather has created wind slab and persistent slab avalanche problems and the avalanche danger is MODERATE near and above treeline, while a LOW danger exists below treeline.   

Our chief avalanche concern is the recently formed wind slabs, which continue to build on leeward sides of ridges and gullies at mid and high elevations.  While these slabs will heal with time it is possible to trigger them on isolated slopes, creating potentially dangerous avalanche conditions.  A secondary problem is persistent slabs due to weak, wet snow below the thin melt/freeze and sun crusts from last week's warm temps.  This layer of wet facets appears to be gaining strength as the weight of the new snow and colder temps start to bond these layers.  We were not able to trigger propagation of this layer in our stability tests over the weekend, but I am not convinced the healing process is complete, which contributes to a MODERATE avalanche danger.  Snowpack variability exists as we travel from slope to slope requiring careful investigation of the zone you plan to play in.  Dig down and see what you're dealing with, as the existence of wet facets below the new snow is cause for concern. Enjoy the day as we keep our fingers crossed for a promising dose of snowfall on Tues and Wed! 

We will issue the next advisory on Tuesday morning, and if you get out into the backcountry, please share any observations with us at toasavalanchecenter@gmail.com or on the "submit observations" tab at the top of the homepage - and Thank You!

Events and Happenings:

Many of you have been asking and we are going to be teaching a Level 1 avalanche class Friday March 31st - Sunday April 2nd.  For more information please email Andy or Graham at andy@taosavalanchecenter.org or graham@taosavalanchecenter.org

Sorry gang, we don't have an avalanche beacon problem set up this week (yet) but will keep you posted as soon as we do.

recent observations

Sunday greeted us with a welcomed 5-7" of moderate density snow, drastically improving the skiing and riding conditions in the backcountry.  Our pal Will made this video explaining his findings on a W aspect below treeline.  The sun crust from Sat is very evident and will likely provide a smooth sliding surface for subsequent new snow.  Thanks Will!  We also noticed the slow, steady growth of cornice and pillow (soft isolated windslabs) at the ridgetops on Sunday, and the TSV Patrol reported good results with explosives, although none of the wind slabs and cornices they triggered stepped down into deeper layers below last week's crust - a good sign.

Saturday morning had folks fired up for a long overdue dose of powder but it didn't last long as warm temps and direct sun made their mark by mid morning.  My partners and I toured around some East aspects near treeline and found "challenging" conditions but a healing snowpack, explained in this video .

Pic; isolated cornice and pillow on ENE face near treeline on Sunday

Pic; wind slab formed Friday on E face near treeline

 
 
Pic; wet facets persist below melt freeze crusts which are starting to heal in most places.
 
 

Pic; Snowpit from Friday on an East Aspect Near Treeline.

 

 

CURRENT CONDITIONS Weather observations from the Wheeler Peak Wilderness between 9000 ft. and 13000 ft.
0600 temperature: 19.3 deg. F.
Max. temperature in the last 24 hours: 28.7 deg. F.
Average wind direction during the last 24 hours: WSW
Average wind speed during the last 24 hours: 17 mph
Maximum wind gust in the last 24 hours: 34 mph
New snowfall in the last 24 hours: 2 inches
Total snow depth: 96.2 inches
weather

Today will be a bit of a transition day with clear sunny skies in the morning, giving way to building clouds and a few snow showers tonight.  Overnight lows look to be in the teens and 20s and we should see a few inches of fresh snow by Wed am with more snow on tap throughout the day wednesday.  Models are a bit conflicting on accumulations for this system, but most agreee that the mountains should see somewhere in the 10-12" range for the storm total.  Winter is not done with us yet!

Two-Day Mountain Weather Forecast Produced in partnership with the Albuquerque NWS
For 9000 ft. to 10000 ft.
  Monday Monday Night Tuesday
Weather: Morning sun becoming partly cloudy in the afternoon. Mostly cloudy with scattered snow showers. Snow likely.
Temperatures: high to 38 deg. F. low to 21 deg. F. high to 33 deg. F.
Wind direction: SW SW SW
Wind speed: 5-10 5-15 5-10
Expected snowfall: 0 in. .2-1 in. 2-4 in.
For 11000 ft. to 13000 ft.
  Monday Monday Night Tuesday
Weather: Morning sun becoming partly cloudy in the afternoon. Mostly cloudy with scattered snow showers. Snow likely.
Temperatures: high 32 deg. F. low to 20 deg. F. high 25 deg. F.
Wind direction: SW SW SW
Wind speed: 5-15 10-15 5-10
Expected snowfall: 0 in. .5-1.5 in. 2-4 in.
Disclaimer

This advisory applies only to backcountry areas outside established ski area boundaries, Click here for a map of the area. . This advisory describes general avalanche conditions and local variations always occur. This advisory expires 24 hours after the posted time unless otherwise noted. The information in this advisory is provided by the Taos Avalanche Center who is solely responsible for its content.