Bollettino valanghe

Banner Summit

Sawtooth Avalanche Center
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Pericolo valanghe

Sun
Alta quota
3 · Marcato
Limite del bosco
2 · Moderato
Sotto il limite
1 · Debole
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Non aggiornato — questo bollettino è scaduto last year. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Watch for and avoid fresh wind drifts—these will be thicker and easier to trigger as you climb in elevation or into wind-exposed terrain.  Triggering a large, wide avalanche is possible on steep slopes facing the northern half of the compass. If the sun comes out today, natural sun-induced loose snow avalanches are possible on very steep slopes, basking in unobscured sunlight. 

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1–2

    Blustery winds today will form fresh, reactive drifts that a person could easily trigger. The likelihood of triggering one of these slides will increase where you find a thicker, stiffer slab of wind-drifted snow—most likely near ridgelines, alpine bowls, and gullies. The thickest and most reactive wind slabs will most likely form in the upper elevations; however, don't rule out finding this problem in wind-exposed terrain features along the middle elevation band. Watch for dunes, drifts, and snow pillows. Cracks shooting out in front of you are a clear sign you've found a wind slab.

     

    (3/20/2025)

    Wind-textured slope near Castle Pk. Gullies like the ones in the photo could harbor a stiff slab of wind drifted snow that a skier or rider could trigger. 

    Photo: Sawtooth Avalanche Center

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1.5–2.5

    It is possible to trigger 2-2.5 foot thick slabs above weak layers of facets or face+cust combinations. You are most likely to find trouble on steep middle and upper-elevation slopes facing the northern half of the compass. Signs of instability like snowpack cracking and collapsing (whumpfing) may not be obvious, and your first sign of instability could be triggering an avalanche. Avalanches could be triggered remotely, from lower-angle terrain above, below, or to the side of steep slopes. Persistent Slabs can release in surprising ways and break much wider than expected. 

    You can manage this problem by seeking lower-angled terrain free of terrain traps such as thick trees, gullies, and cliffs. 

    (3/18/2025) A wide, slab avalanche near Banner Summit on Bull Trout Pt. E @ 8,500'. Photo: Sawtooth Avalanche Center

Avalanche Discussion

You are most likely to trigger an avalanche today where the wind has form thick drifts. Expect drifts to be thicker and more reactive as you climb in elevation, or into wind exposed terrain features, be wary of stepping into terrrain where you find these thicker drifts of new snow—especially near ridgelines, gullies or alpine bowls. Blustery winds will be forming drifts in odd places, don't rule out finding this problem near the top of treed slopes along the middle elevation band. 

With the addition of new snow and wind, the likelihood of triggering a larger, wider and thicker persistent slab avalanche isn't out of the question. Buried weak layers haven't had a substancial break from loading, and triggering one of these slides remains possible. You can hedge you bets by seeking lower-angled terrain, or slopes free of terrain traps such as gullies, thick trees, or cliffs. 

When the sun comes out this afternoon, natural sun induced loose snow avalanches, sluffs, are possible in very steep craggy terrain basking in direct sun. While these slides shouln't be large enough to bury a person, they could pack a punch and ruin your day. 

Regioni coperte