THIS AVALANCHE ADVISORY EXPIRED ON March 1, 2017 @ 5:53 am
Avalanche Advisory published on February 28, 2017 @ 5:53 am
Issued by Graham Turnage - Taos Avalanche Center

Considerable avalanche danger exists at all elevations today due to storm slabs.  Natural and human triggered avalanches are likely.  Over 16" of new snow and strong winds have created unstable storm slabs and this trend will continue today with more snow expected and winds gusting into the 60s.  Careful snowpack evaluation, cautious route-finding and conservative decision-making are essential.

3. Considerable

?

Above Treeline
Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.

3. Considerable

?

Near Treeline
Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.

3. Considerable

?

Below Treeline
Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.
    Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.
  • 1. Low
  • 2. Moderate
  • 3. Considerable
  • 4. High
  • 5. Extreme
Avalanche Problem 1: Storm Slab
  • Type ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

Storm totals as of 5:30am are in the 17" range with over 1.5" of SWE, and winds are howling, gusting into the mid 60s. This new snow is falling on a variety of hard, smooth crusts as well as low density snow from Monday, and will struggle to bond to these underlying surfaces. This will create widespread instability as this new load needs time to settle.  Strong winds and more snow today (4-10") will continue to build unstable storm slabs, which will likely be 3-4 feet thick in the alpine.  We expect to see avalanches within this new snow today, and recommend very conservative terrain choices. 

 

advisory discussion

14 - 18" of new snow and strong winds have created unstable avalanche conditons at all elevations.  With over 1.5" of Snow Water Equivalent (SWE) and winds gusting into the 60s, we expect to see both natural and human-triggered avalanches today.  Weather models are calling for another 4-10 inches of snow and continued strong winds.  This brings the avalanche danger to CONSIDERABLE on all aspcets and elevations for today due to storm slabs.  Monday's 4+/- inches of snow came in cold and light,  and is now capped by another foot or more of wind effected, denser new snow.  This has created areas of an "upsidedown" surface snowpack - an unstable situation.  Storm slabs at upper elevations will likely build to 3-4 feet today, and steep, wind loaded terrain should be avoided.  Careful snowpack evaluation, cautious route finding, and conservative decision making are essential today.  Be safe out there today all!

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

Monday brought us an unexpected 3-5 inches of low density snow in the mountains, accompanied by strong W winds.  These winds were building touchy ridgetop cornices and creating unstable surface conditions on steep rollovers and convexities.  Check out Andy's video explaining Monday's findings.   We found the new snow was not bonding well to the underlying crusts, and although there was not much weight to move around yesterday, that will certainly change today with more snow and wind.

Below the new snow surface lies a variety of melt freeze and wind crusts, coupled in many places with a layer of facets (see pics below).  Stability tests from recent days suggest this faceted layer is willing  to propagate and we suspect it will do so with the added weight of today's storm slabs.

Deep layers of concern in the snowpack have shown signs of healing, and we have not been able to initiate failure of these layers since last week's melt/ freeze cycle.  See Graham's video from Friday about this.  This is reassuring but areas of weak snow may still linger on isolated terrain features, mostly rock ribs and thin spots. 

Pic; cornice/ pillow formation from Monday.

Pic: Buried NS Facets formed before Monday night's storm.

 

Pic: Melt-Freeze crust on a East aspect below treeline w/ facets below the crust.

 

 

 

Weather and CURRENT CONDITIONS
weather summary

The storm came through as expected and 24 hour storm totals are 14-18", and the wind is honking.  It's snowing and blowing in the mountains this morning, and this will continue today, with another 4-10" of snow expected and gusts into the 60s.  Temps look to top out in the 20s to low 30s, before overnight lows dip into the single digits.  As the storm exits this afternoon / evening a clearing trend will bring sun and subsiding winds for Wednesday.  Enjoy this awesome dose of Winter weather!

 

Weather observations from the Wheeler Peak Wilderness between 9000 ft. and 13000 ft.
0600 temperature: 19.1 deg. F.
Max. temperature in the last 24 hours: 19.4 deg. F.
Average wind direction during the last 24 hours: WSW
Average wind speed during the last 24 hours: 29 mph
Maximum wind gust in the last 24 hours: 66 mph
New snowfall in the last 24 hours: 17 inches
Total snow depth: 87 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Albuquerque NWS
For 9000 ft. to 10000 ft.
Tuesday Tuesday Night Wednesday
Weather: Snowy and windy. Partly cloudy with isolated snow showers. Sunny.
Temperatures: high to 32 deg. F. low to 5 deg. F. high to 34 deg. F.
Wind Direction: W W W
Wind Speed: 10-30, gusts in the 60s 5-25 5-15
Expected snowfall: 3-9 in. .2-.6 in. 0 in.
For 11000 ft. to 13000 ft.
Tuesday Tuesday Night Wednesday
Weather: Snowy and windy. Partly cloudy with isolated snow showers. Sunny.
Temperatures: high to 24 deg. F. low to 2 deg. F. high to 22 deg. F.
Wind Direction: W W W
Wind Speed: 20-35, gusts in the 60s 10-25 10-15
Expected snowfall: 4-10 in. .4 - .6 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.