Bollettino valanghe

East Slopes North

Northwest Avalanche Center
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Pericolo valanghe

Sat
Alta quota
4 · Forte
Limite del bosco
4 · Forte
Sotto il limite
3 · Marcato
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In sintesi

Stay off and out from under wind-loaded slopes, and pay attention to warning signs like natural avalanches, cracking, and collapsing. Stick to wind-sheltered terrain at low elevations, well out from under overhead avalanche paths. Very strong west winds are overloading the weak snowpack, causing very large and deadly natural avalanches.

Problemi valanghivi

  • Persistent Slabs

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

    Avalanches in wind-loaded terrain will be very dangerous and will run naturally. They could break widely across terrain and be very large, even unsurvivable. If you venture into the mountains, be sure of your ability to avoid avalanche terrain, including any overhead, wind-loaded slopes and avalanche paths. Put a wide buffer of terrain between yourself and any wind-loaded slope steeper than 30 degrees. You could trigger avalanches from far away, and they could come down from above. 

    The most dangerous areas will be above 5,000ft where the wind is depositing snow and forming stiff slabs. Weak faceted snow and surface hoar are resting on a crust, about 1.5-2 feet below the surface. Strong westerly and swirling winds will continue to stress these weak layers as slabs form on lee aspects, even well-below ridgelines. At low elevations, these avalanches may act more like your average storm or wind slab, but you may be able to trigger them longer than normal.

    (2/26/2026)

    A couple of large, natural avalanches on a leeward slope. Note blowing snow and crowns well below the ridgeline. This likely ran on a weak layer above the 2/7 crust, ~2 feet below the surface. Cutthroat Lake. ESE, 7,000ft

    Photo: NCH

Avalanche Discussion

Ongoing westerly winds will dominate the weather at least through Friday. This wind event is so significant that the drifted slabs are adding stress to the weak, underlying snowpack. Stay diligent to look for recent avalanches, blowing snow, and give yourself greater margins of safety.

Since midweek, there's been a widespread cycle of natural and triggered avalanches in the Washington Pass area, and possibly near Hart's Pass. On the 26th, observers reported numerous natural avalanches on leeward, wind-loaded slopes near Cutthroat Lake and in Cedar Creek. Many were large to very large, and some had wide crowns deep enough to have run on a suspected persistent weak layer. Some avalanches were shallower, more typical of wind slabs at the base of cliffs. 

A decent share of the recent avalanches are confirmed or suspected to have run within weak, faceted snow and surface hoar over the 2/7 crust. Over the weekend, there was a report of a widely propagating, but shallow avalanche near Heather Pass.  On the 22nd, observers near Harts Pass triggered an avalanche on surface hoar, buried 8-10" below the surface. As of the 25th, wind-drifted snow began to stress these weak layers, bury them deeper, and create very dangerous conditions.

1-2 feet below the surface is a weak layer over a crust (February 7th). Immediately above the crust are weak faceted grains and, in some places, surface hoar. The January 28th crust is thicker and another 6-12" deeper.  On southerly aspects, there are more crusts and less dry, weak snow on the surface. West of Washington Pass, overall, the layers will be deeper, with thicker crusts and more snow between them. Farther east, in places like the Chewuch and Twisp River drainages, the snowpack is shallower and weaker. We have little recent information in the eastern mountains and suspect a very weak snowpack.

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