THIS AVALANCHE ADVISORY EXPIRED ON March 4, 2017 @ 5:55 am
Avalanche Advisory published on March 3, 2017 @ 5:55 am
Issued by Andy Bond - Taos Avalanche Center

MODERATE avalanche danger exists at all elevations. Human triggered wind and persistent slab avalanches remain possible today near and above treeline. Below treeline and on solar aspects wet loose avalanches will become possible as the temperatures begin to warm.  Evaluate snow and terrain carefully and make a plan to avoid areas of concern.  

2. Moderate

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Above Treeline
Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.

2. Moderate

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Near Treeline
Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.

2. Moderate

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Below Treeline
Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
    Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
  • 1. Low
  • 2. Moderate
  • 3. Considerable
  • 4. High
  • 5. Extreme
Avalanche Problem 1: Persistent Slab
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Lower density snow from Monday morning is still lingering in our snowpack at mid and upper elevations that is now buried by a 2 to 4 foot stiffer slab that formed from the storm and strong winds on Tuesday.  This weak layer is sitting on top of hard crusts in many spots, that formed prior to this last weeks snowfall. Most of the widespread avalanche activity on Tuesday and Wednesday ran on this layer.  

A smaller surface wind slab could be enough weight to step down into this deeper layer.  Using your probe or ski pole is good way to identify if the slope your traveling on has this snowpack structure of strong over weak. Avoid likely trigger points near rocks where the slab is shallower.      

Avalanche Problem 2: Wind Slab
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On Thursday small 10" wind slabs were triggered in the Williams Lake Drainage.   These wind slabs formed from Wednesday nights NW wind.  Winds did pick up again last night out of the SW this time.  Most of the SW and W aspects are void of transportable snow, but as is often the case winds can swirl in our mountain range.  Slabs of wind-drifted snow will be found near ridgetops, cross-loaded terrain features and mid slope convexities.  Pay attention to obvious signs like wind-drifted pillows, shooting cracks and sounds of "whumphing" collapses.

An obvious wind drifted pillow on a NNE Aspect that was triggered on Thursday

Avalanche Problem 3: Loose Wet
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Temperatures will warm significantly today, combined with our strong southern latitude sun, small wet loose avalanches will become possible today below treeline and on solar aspects at mid elevations especially in steep rocky terrain.  Avoid areas where the snow becomes wet and manky and head to shadier aspects.  

 

  

 

advisory discussion

Not all MODERATE avalanche dangers are created equal.   Today is not the day to think that moderate means green light.  Lower density snow from Monday morning is now buried by a 2 to 4 foot slab.  Stability tests are still indicating that you can initiate collapse and propagation of this weak layer that is sitting in most spots on a hard smooth crust. Recently formed wind slabs in the alpine should become less reactive today but compounds our avalanche problem.  A smaller surface wind slab in extreme terrain could spell disastrous consequences or has the possibility of stepping down into deeper layers. See Andy's Video from Thursday.  

Natural avalanche activity has subsided with our last natural avalanche observed on Wednesday.  Monday into Tuesday's storm was impressive with 18 to 30" of snow and over 3" of SWE leaving our mountains covered in a fresh coat of white snow. We're back to our usual avalanche problems of wind and persistent slab.  The potential is there for a large and destructive persistent slab avalanche today.  Conditions like we have leave me wondering if I can get away with skiing the slope.  It's not always an easy decision with a lot of factors at play pulling you in different directions.  It only takes one time to hit that "sweet" spot and release a large catastrophic avalanche. Assess each individual slope you plan to travel on evaluating the snowpack and terrain.       

As we get new snow in March, our strong sun combined with warming temperatures following storms will make Loose Wet avalanches more of a concern. Today will be the first warm day with temperatures reaching the mid 40's below treeline.  Expect to see roller balls below treeline and on steep solar aspects as the day starts to warm.  This problem can be easily avoided by sticking to shady aspects

 

If you're interested in how much snow we've gotten this year check out our recent blog post.  This was written before this last storm, so add 25.5" of snow and 3.15" of SWE to the totals from February which should bring us right around average!

We have a fresh beacon problem out at TSV for the week of feb 28 - mar 6 - check it out and keep your beacon skills sharp!

If you get into the backcountry, please drop us a line at Taosavalanchecenter@gmail.com or on the "Submit Observations" tab at the top of the homepage.  Your field observations are extremely helpful, no matter how simple, and we thank all of you who have shared.

If you're looking to get some exercise and support a great cause look into the Ben Myers Ridge-A-Thon.  This event has been going on now for 20 Years. Come hike the ridge at Taos Ski Valley March 17 & 18th and raise some money that benefits our community!

recent observations

Thursday was another sunny, calm day, with a cold clear night.  Winds picked up Wednesday night out of the NW and formed some sensitve wind slabs above treeline.  Stability tests are still indicating that the weak layer from Monday's lower density snow is still there and once collapse is initiated it is willing to propagate.

Wednesday was a sunny and calm day.  A cold clear night on Tuesday really dried the snow out and already were seeing these storm slabs settle and consolidate especially below treeline.  We were able to get up around 12,000' on a West aspect where we found a little more than 2 feet of storm slab sitting on a knife hard melt-freeze crust.  In snow pits we were not able to initiate collapse or propagation in the storm slab See Video. However, inbounds control work at TSV on Wednesday did produce some 3' storm slab avalanches mostly on northerly and East aspects.  These were more stubborn than the widespread instability from Tuesday.    

STORM RECAP:  Storm totals from Monday through Tuesday ranged from 18 - 30" of new snow with about 3" of Snow Water Equivalent (SWE). Strong SW winds gusting into the 60's also accompanied this storm adding to storm totals especially above treeline. Tuesday was an active day with widespread "whumphing" collapses and shooting cracks as well as remote triggering storm slab avalanches See Video.  18 to 24" of snow was observed while touring in the Williams Lake Area. The snow that fell Monday night into Tuesday had some body and weight to it even though it was still pretty low density.  This subtle density difference between the couple of inches of snow that fell in the morning on Monday was all that was needed to create a weak layer. Check out Andy's video explaining Monday's findings.   

Pic: Snowpit from a North Aspect near treeline on Thursday.  The storm slab is 92cm thick with 4F to F hard snow.  I marked the weak lower density snow that is still there from Monday morning.  ECTP 15 SP where the line is marked.

Pic: An obvious wind-drifted pillow on a NNE aspect around 12,800' from Thursday

Pic: Snowpit from NNE Aspect around 12,800' from Thursday.  10" 4F wind slab on top with buried near surface facets beneath it.  We triggered this wind slab with a ski cut but had an ECTP1 SC on this layer. 110cm down is a 5" weak layer of lower density facets that fell Monday Morning.  On this layer we got ECTP 20 SP and PST 25/110 END SC.   

 

Weather and CURRENT CONDITIONS
weather summary

High pressure aloft overhead today will bring another sunny New Mexican sky.  Temperatures today will warm into the mid 40's below treeline.  Winds should back off again during the day (5 to 15 MPH) out of the west.  An even warmer day is in store for Saturday before the winds return for Sunday!

Weather observations from the Wheeler Peak Wilderness between 9000 ft. and 13000 ft.
0600 temperature: 16.4 deg. F.
Max. temperature in the last 24 hours: 26 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 12 mph
Maximum wind gust in the last 24 hours: 35 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 91.7 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Albuquerque NWS
For 9000 ft. to 10000 ft.
Friday Friday Night Saturday
Weather: Sunny Mostly Clear Mostly Sunny
Temperatures: high to 44 deg. F. low to 17 deg. F. high to 48 deg. F.
Wind Direction: SW SW W
Wind Speed: 5 - 15 5 - 15 5 - 20
Expected snowfall: 0 in. 0 in. 0 in.
For 11000 ft. to 13000 ft.
Friday Friday Night Saturday
Weather: Sunny Mostly Clear Mostly Sunny
Temperatures: high to 34 deg. F. low to 16 deg. F. high to 39 deg. F.
Wind Direction: W SW W
Wind Speed: 5 - 15 10 - 20 10 - 25
Expected snowfall: 0 in. 0 in. 0 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.