Bollettino valanghe

Northern New Mexico

Taos Avalanche Center
Vedi sulla mappa

Pericolo valanghe

Fri
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
2 · Moderato
Open full map
Non aggiornato — questo bollettino è scaduto 6 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

We currently have two buried persistent weak layers that are capable of producing large, dangerous, and unsurvivable avalanches. Avalanches that fail on these layers could propagate wide distances and take the entire snowpack with it. Slab thickness is not uniform across our terrain from strong wind events or repeater avalanche paths harboring a shallower snowpack and this has created a lot of uncertainty underfoot. You are far more likely to trigger an avalanche in areas where the slab is thinner.  Due to the uncertainty and high consequences we recommend avoiding terrain approaching 35 degrees or greater where this problem exists.   

Problemi valanghivi

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    2–3

    24 to 36+ inch slabs rest over two buried weak layers of concern. The first layer you'll encounter is a layer of 1mm Near-Surface Facets buried 60-70cm from the surface. The second layer is 2-3mm large-grained facets buried 80-100cm down. This layer has been the more reactive and concerning in our long column tests. Due to the depth and length of time since our last loading event, it's becoming increasingly difficult to trigger an avalanche on this layer. However, when or if you are able to, our long column tests have illustrated a frightening ability to propagate still, with our slabs collapsing and shooting off the column with little resistance. 

    The most likely areas to trigger these avalanches are on northwest through east aspects near and above treeline in areas where the slabs are thinner and you are more likely to impact these buried weak layers. These are also the most likely areas to trigger avalanches approaching D3 in destructive size. West and southeast aspects should be given respect as well but an overall shallower snowpack (meaning smaller avalanches) and recent strong solar events have aided in decreasing the likelihood. 

    Pay attention to signs of instability such as shooting cracks and audible collapses. Stay out of terrain steeper than 35 degrees 

     

     

     

    Faceted weak layers between harder slabs deeper down in the snowpack with last week's storm slabs on top.

Avalanche Discussion

Last evening's storm never quite developed and we received 1 to 2 inches of new snow from 0.10 to 0.25 inches of SWE. Winds were strong to extreme with average speeds in the 30's and 40's with gusts exceeding 60 mph. However, we just didn't receive the anticipated accumulations that initially gave us concern and for that reason, we are dropping the avalanche danger back down to "Moderate" today. 

You may be able to find small pockets of wind slab on the leeward sides of ridges and cross-loading features above treeline but these will be fairly harmless baring they don't sweep you over consequential terrain such as a cliff band. It's unlikely you'll encounter any significant new wind loading due to the lack of available snow for transport but if you do it's best to avoid this terrain for now. 

The greater concern at the moment is our persistent slab avalanche problem and we have two potential layers of failure within our snowpack. The most concerning of the two is a layer of 2-3mm large-grained facets that are buried roughly 80-100cm's down. The other layer of concern is 1mm near-surface facets buried 60-70cm's down. I hesitate to talk about the average burial depth of these layers as it varies a lot from slope to slope. The depths I've given reflect a slope that has not avalanched and has the 24 to 36 inches of storm snow resting on top.  But the fact is that strong wind events and repeater avalanche paths that have run multiple times this season have created variable, often shallower snowpack structures. I'm talking about this because it's in these areas where the snowpack is either overall shallower or the slab is thinner where you are most likely to trigger one of these avalanches. If you are able to trigger a persistent slab avalanche right now it will likely be large, destructive, and unsurvivable.  So to sum all that up we have high consequences accompanied by a lot of uncertainty.

It's for these reasons we are giving this avalanche problem a wide berth right now. Avoiding terrain approaching 35 degrees or greater and watching for signs of instability such as shooting cracks and audible collapses are important. These obvious signs of instability are becoming more infrequent in our travels but experiencing one shouldn't be brushed off. This is also an indication that remotely triggering an avalanche from an adjacent slope or from below is still possible. Equally as important right now, especially below treeline, is identifying and avoiding terrain traps no matter how big or small. Even small slopes above a creek that may seem harmless can produce enough snow to bury you. It's tricky conditions out there, keep it conservative and stay safe everyone!

Regioni coperte