THIS AVALANCHE ADVISORY EXPIRED ON January 22, 2018 @ 5:59 am
Avalanche Advisory published on January 21, 2018 @ 5:59 am
Issued by Andy Bond - Taos Avalanche Center

MODERATE avalanche danger exists at all elevations due to storm slab and persistent slab avalanches. Human triggered avalanches are possible.  This is the first major storm of the season, providing the first real test to our weak, thin snowpack. If we see the upper end of the forecasted snow amounts, expect avalanche danger to rise throughout the day.  Evaluate snow and terrain carefully, identify features 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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During the last week of high pressure, our weak layers have become dormant.  Last night's and today's snow will be enough weight to reactivate these weak layers. Human triggered persistent slab avalanches will be possible today.  Watch for unstable snow on isolated steep slopes above treeline on north to east aspects, including cross-loaded gullies, concave bowls, and beneath ridgelines. These are the places holding the most snow right now from winds depositing snow from early season snow storms.  The snowpack in these areas has a poor snowpack structure-- basically strong over weak-- where we have slabs resting over weak sugary faceted snow

The tricky part about today, is that it will be tough to identify where the old snow was before this storm.  These persistent slabs were only located on specific slopes and not widespread.  If you plan on getting out and playing in the new snow today assume every slope near and above treeline has this poor snowpack structure.  Take the time to dig down into the snow and assess if the new snow has fallen on old snow.  Look for slabs that exist over weaker snow as these will be the slopes with the most concern today. If you find this set-up or experience shooting cracks, whumpfing and collapse it's best to avoid these slopes. 

Avalanche Problem 2: Storm Slab
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At 5AM 5 to 7 inches of snow has fallen with about .4" of snow water equivalent.  The snow that fell overnight, came in light with temperatures falling into the single digits.  Transportable wind speeds in the 15 to 20 MPH range will be strong enough to move this new snow around creating storm slabs. We could see up to an additional foot of snow throughout the day. The new snow is falling on a variety of surfaces from bare ground, crusts to cohesion-less facets. Where the new snow is falling on our older snow will be the biggest concern, especially in areas where we have a storm slab resting on top of weak sugar-like snow.  If we see the upper end of the forecast amounts, areas where the new snow is falling on bare ground could become a concern.  As temperatures warm throughout the day, we can expect to see density changes within the new snow and the potential for an upside down storm, with the heavier snow resting on top of the low density snow that fell last night.

Avoid steep slopes like convex rolls where you find 8" or more of new snow or snow pillows.  Any storm slab avalanche would be small, but has the potential of stepping down into older layers creating a larger more destructive avalanche.  

advisory discussion

Finally a decent looking storm for us here in Northern New Mexico!  We have reports of 6 to 8 inches of new snow early this morning with deeper drifts from the moderate to strong winds accompanying this storm.  The snow overnight fell as low density snow with about .4" of SWE.  If we see the upper end of the forecasted amount, we could see snow totals well over a foot by tonight.  This is the first major storm of the season, and first real test to our weak and shallow snowpack.  It's great to see our mountains covered in white again, but with that will also come an increase in avalanche danger.  It's been a rough start to our season, but it's a good idea to get your head back into the avalanche game.  Dust off your gear, make sure your beacon has batteries and all your rescue gear is in working order.  Remember good travel techniques like only exposing one person at a time.

Human triggered persistent slab and storm slab avalanches are possible today, and it's not out of the realm of possibility to see some natural avalanche activity.  We could also see small loose snow avalanches in areas that haven't been impacted by the wind. The real concern today is where the new snow has fallen on our lingering snow from previous storms. If you haven't gotten out for a walk yet this year, I don't blame you.  The season history of our snowpack can be summed up as thin, weak and highly variable.  Snow from earlier this year can be found above 11,000' on north through east aspects. The old snow consists of weak sugar-like snow or slab/weak layer combinations that for the most part are not continuous.  This will limit the propagation of any avalanches today, but also means that each slope needs to assessed on an individual basis.  Terrain features that do contain a deeper snowpack from previous storms are incredibly weak and will not be able to handle much weight from this storm.   

With the new snow it will be difficult today to identify where the previous snow existed.  Expect the unexpected, as we could see avalanches start in atypical start zones. With our highly variable and thin snowpack things can change quickly where you go from a shallow snowpack to a surprising amount of snow.  We have lots of trigger points right now that could initiate a larger deeper avalanche that could cause serious injury.  It sounds weird to say the season is just starting at the end of January, but we still have several months of skiing in front of us.  Ease into it as we still have a thin snowpack where lots of ground hazards exist.  Even a small avalanche today could cause serious injury.   

recent observations

There hasn't been much going in the last week of high pressure.  We have a thin, weak and highly variable snowpack on north aspects near and above treeline.  Buried weak layers have become dormant, but will become reactive with the new snow and added weight. 

Weather and CURRENT CONDITIONS
weather summary

A stout disturbance from the Pacific has made its way into NM with 5 to 7" of snow already haven fallen by 5AM.  Temperatures are starting off in the single digits at 10,000' and will gradually rise throughout the day.  Snow showers are supposed last throughout the day and tapper off tonight.  We could see anywhere from a few more inches to up to a foot of additional snow.  I'm thinking more on the lower side.   Strong W to NW winds today with the possibility of gusts in the 60's.  Temperatures will be cold tonight as the storm makes its exit.  Sunshine will return on Monday.     

Weather observations from the Wheeler Peak Wilderness between 9000 ft. and 13000 ft.
0600 temperature: 7.7 deg. F.
Max. temperature in the last 24 hours: 31.7 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 18 mph
Maximum wind gust in the last 24 hours: 55 mph
New snowfall in the last 24 hours: 5-7 inches
Total snow depth: 14 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Albuquerque NWS
For 9000 ft. to 10000 ft.
Sunday Sunday Night Monday
Weather: Numerous Snow Showers Mostly cloudy... Scattered snow showers in the evening Mostly Sunny
Temperatures: 29 deg. F. 7 deg. F. 30-35 deg. F.
Wind Direction: W NW W
Wind Speed: 5-25 5-20 5-20
Expected snowfall: 3-13 in. .5-1.2 in. 0 in.
For 11000 ft. to 13000 ft.
Sunday Sunday Night Monday
Weather: Numerous Snow Showers... Areas of blowing snow Mostly cloudy. Scattered snow showers in the evening. Areas of blowing snow in the evening. then cloudy with widespread snow showers after midnight. Areas of blowing snow though the night. Mostly Sunny
Temperatures: 17-22 deg. F. 5 deg. F. 21-26 deg. F.
Wind Direction: W NW NW
Wind Speed: 15-25 10-20 10-20
Expected snowfall: 5-13 in. .7-1.7 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.