Bollettino valanghe

Blues

Wallowa Avalanche Center
Vedi sulla mappa

Pericolo valanghe

Mon
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
2 · Moderato
Open full map
Non aggiornato — questo bollettino è scaduto 4 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Triggering a newly formed wind slab near and above the treeline will be likely today where the wind has packed the snow into a more cohesive slab.  Visual clues of wind slab formation include cornices, pillows, dune-like formations, and shooting cracks from your skis, board, or machine.   While becoming more unlikely, it remains possible to trigger a deeper and more destructive avalanche on one of several persistent weak layers that are buried 2-8 feet within our snowpack.   Increase your safety margins today; look for low-angle terrain without overhead hazards, limit exposure to steep slopes, and avoid regrouping in avalanche runout zones.  

Today's avalanche forecast is sponsored by Terminal Gravity Brewing, in Enterprise, OR.  

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1–2.5

    Fresh wind slabs will be touchy and increase in size and distribution throughout the weekend.  Expect to find wind slabs near and above the treeline and use visual clues such as shooting cracks, harder snow over softer snow, dune-like formations, and drifts to understand the distribution.  With the likelihood of strong winds today, expect to find wind slabs develop in locations that typically are less prone to wind slab development.  

    (1/7/2023)

    Photo shows some of the visual clues to look for when a wind slab problem is in the forecast.  

    Photo: VM

  • Deep Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–3

    Low likelihood, high consequence.  The most recent natural avalanche that failed on weak facets near the ground occurred on 12/30 on a 36-degree slope on a NE aspect at 6800' in the vicinity of Wing Ridge in the Northern Wallowas.  On Friday WAC Forecaster Nick Burks took a look at this natural avalanche and observed that it had failed on weak faceted snow near the ground.  You can read Nick Burks professional observation here.

    Pro Observer Towner Menefee posted an observation from the Northern Wallowas where he found alarming results in his snowpack tests, with the entire season snowpack failing near the ground.  

    If you take the time to read their observations you will note there is a level of inconsistency with test results.  This is why the forecasting team and local ski guides are sticking to simple terrain, less than 30-degree slopes, and giving themselves large safety margins.   

    (1/6/2023)

    Crown and flank of an avalanche reported on 12/30 on Wing Ridge.

    Photo: NB

Avalanche Discussion

Caleb Merrill did an excellent job informing us of the degree of uncertainty we currently face with our deep persistent slab problem.  I would strongly recommend you read his breakdown of the current conditions in our snowpack blog.    Although some of you may be tired of hearing about this deep persistent slab, it's not time to disengage.  Within the last 10 days, we have seen natural and human-triggered avalanches across our forecasting zones failing on either weak faceted snow near the ground or buried surface hoar near the Christmas Crust.  

We need to see roughly three weeks, accompanied by a couple of significant storms (or wind events) to put this avalanche problem to rest.  This requires all of us to remain engaged and curious.  You will likely see folks out high marking, skiing, riding slopes greater than 30 degrees and not triggering avalanches.  Possibly they have no understanding of avalanche terrain, avalanche problems, or have not read the forecast.  Ignorance is bliss, and we can receive different types of feedback after a day in the mountains that gives us a certain bias about the conditions.  At the end of the day it's good to ask yourself did we make good decisions, or did we just get lucky?

Truth be told we can and will continue to find good riding conditions and can have a great day in the mountains avoiding slopes that are steep enough to slide, and not hanging out in runout zones.  

Regioni coperte