Bollettino valanghe

West Mountains

Payette Avalanche Center
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Pericolo valanghe

Sun
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
1 · Debole
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In sintesi

It's possible to trigger a shallow wind slab on upper elevation slopes, near corniced ridgelines & steep rollovers. 6-12-inch-thick wind slabs are most likely above 7,500 feet on east-facing slopes. Pay attention to cross-loading. Triggering a 2-foot-thick persistent slab avalanche is unlikely, but not impossible. Identify areas in the terrain where persistent slabs exist and practice safe travel habits. Plan for uncertainty with today's quickly changing weather.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–1.5

    The West Mountain zone has received just a few inches of new snow over the past 48 hours. Strong W/SW winds have been blowing over the past few days. The mountains could see a few more inches today with strong westerly winds. You may find wind slabs 6-12 inches thick on east-facing slopes above 7,500 feet. Wind slabs will be most sensitive just below corniced ridgelines. Look for clues of wind-affected snow such as drifts, dunes, pillows, and freshly-built cornices. Watch for signs of instability like shooting cracks from your skis, board, or sled. If you're observing signs of a wind slab, find another aspect away from wind-drifted snow.

    New snow has fallen on crusts across multiple aspects and elevations. Pay attention to how well the new snow has bonded to the underlying crusts before committing to steep slopes. Strong winds and local terrain features can alter the prevailing wind direction. This recent observation from Lick Creek identifies a wind slab avalanche on a cross-loaded slope. Pay attention to cross-loading and wind-loading on unsuspecting slopes. 

    (3/12/2026)

    Strong WSW winds were moving snow through most of the day above 7,000'.

    Photo: George Halcom

  • Persistent Slabs

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

    Triggering a large persistent slab avalanche is unlikely. Unlikely does not mean impossible. A layer of surface hoar buried on 2/14 now sits about 1.5–2 feet deep. This layer was responsible for many large avalanches over several weeks during late February. These persistent slab avalanches occurred mainly on wind-loaded terrain that faced NW–NE–E above 7,000 feet. You're most likely to trigger a persistent slab avalanche in steep, wind-loaded terrain where the slab is thin (think shallow, rocky terrain). Triggering a 2-foot-thick avalanche would be destructive with bad outcomes. This is the classic low likelihood/high consequence scenario.

    Signs of instability may be absent, and slopes with multiple tracks could still produce a large avalanche. Reduce your risk by identifying areas where this problem exists (upper elevation, north-facing, rocky, wind-affected alpine terrain, with slopes steeper than about 35°). Travel through this terrain should be conservative and intentional. Be especially careful where these terrain features overlap with terrain traps like trees, rocks, and gullies. Spread out and travel one at a time in avalanche terrain.

    (2/26/2026)

    Riders remote triggered this D2.5 avalanche near frog lake north of McCall on Thursday Feb 26th.

    Photo: Payette Avalanche Center

Avalanche Discussion

Skunked again! The moisture associated with an atmospheric river has stayed to our north. Storm totals thus far have been underwhelming (2-4 inches over the past 3 days). Rain/snow lines climbed up to ~7,000 feet on Thursday. A few inches of wet snow fell above 7,000 feet. Strong W/SW winds accompanied new snow. A cold front is bringing another shot of snow with strong west winds this morning. The West Mountain zone could see 3-6 inches (0.5"SWE), with west winds gusting over 40 MPH. Before this storm, widespread melt-freeze crusts were observed across multiple aspects and elevations. Depending on the aspect and elevation, new snow may not be bonding well to underlying crusts. Dig into the new snow with your hand or pole to see how well it's bonding to recently buried crusts. 

Today, it's all about timing. A cold front will bring rain/snow with strong winds. Uncertainty with the weather forecast means uncertainty with the avalanche forecast. Although models indicate new snow amounts will be light (3-6 inches), snow showers could be heavy and coupled with strong west winds. This quick-hitting cold front could build shallow wind slabs quickly. The exact amount of accumulation, rain/snow levels, and timing are all fairly uncertain. Snow surfaces below ~7,000 feet are likely still soft and wet this morning. Wet loose avalanche activity below 6,500 feet will be something to consider this morning, before temperatures drop. New snow could "slab up" quickly with strong winds at upper elevations. Today, the weather dictates the avalanche hazard. When uncertainty exists, it's a good time to slow down. If you're traveling in the mountains today, have alternative travel plans, be curious, and expect to be surprised.

Continue to hedge your bets today by carefully identifying terrain where persistent slabs may be lurking (steep, rocky, north-facing slopes, above 7,000 feet, that are wind-loaded). The only sure way to outsmart this avalanche problem is by avoidance. You can identify terrain where this problem exists and choose to avoid that terrain. You're unlikely to observe signs of instability, and previous tracks on a slope don't indicate it's inherently safe. With deeper, persistent slabs, snowpack tests may provide inconclusive results. Never base a go or no-go decision on one single point of data (i.e., one snowpack test). If avoidance is not your style and you're losing patience with the lingering, persistent slab problem, then you need to be intentional about how you move through the mountains. Safe travel practices are how we build wider margins of safety. Safe travel includes things like: checking to make sure everyone is carrying adequate rescue gear, spreading out and traveling one at a time on steep slopes, regrouping in safe areas away from runouts, identifying and avoiding terrain traps, and developing a plan with your travel partners. 

If you're out in the mountains, submit an observation on our website or through the Avy App. Tag us #payetteavy

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