Bulletin d’avalanche

East Slopes South

Northwest Avalanche Center
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Danger d’avalanche

Sun
Alpin
2 · Modéré
Limite forestière
2 · Modéré
Sous la limite
Sans niveau
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Périmé — ce bulletin a expiré 4 months ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

Anticipate the increasing likelihood of encountering wetted and weakened snow on all aspects and elevations as the day progresses. Slabs of wind-drifted snow may still exist in exposed, upper-elevation terrain, which, if triggered, could entrain wet snow on their way down. Have a route plan that allows you to easily move to lower-angle at any point in the day if you don’t like what you see. Lower elevations lack sufficient snow coverage for avalanche hazard to exist.

Problèmes avalancheux

  • Loose Wet

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1–1.5

    After a few days of temperatures slowly ticking up and teasing gorgeous spring weather, Saturday will finally be the day we get it. Some cloud coverage on Friday night will limit surface crust formation, making it easier for conditions to break down throughout the day. This late in the season, and for how warm it's going to get, don't be surprised to see surfaces warming and weakening on northerly slopes. These aspects may actually be the most reactive on Saturday, as more southerly slopes have already seen a decent amount of sunshine, or may just lack snow altogether. Hazard is low at lower elevations due to a lack of snow and minimal recent snowfall.

    Watch for surfaces that feel increasingly dense and sticky. Chunks of snow falling from terrain features or rollerballs tumbling down from your equipment are a sure sign of increasing instability. These avalanches should be limited in size, but they could run far on an underlying crust. You can reduce your risk by traveling earlier in the day or sticking to shadier slopes. 

    Recently formed cornices along ridgelines are susceptible to falling suddenly due to warming. Don't linger underneath these, or other cliffy terrain that is holding snow.

    (4/15/2026)

    An intentionally triggered wind slab that entrained additional wet loose snow on its way 

    Photo: Payton Schiff

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1–2

    Wind slabs were reactive on Wednesday in neighboring zones, and additional wind transport was observed in the following days. Slabs could fail either on a mid-storm layer or on a crust buried 1-2 feet below. If triggered, they could entrain wet loose snow on their way down and grow bigger than anticipated. The closer you are to the Cascade Crest, the thicker slabs will be. Hazard is generally low to the east, where less snow accumulated.

    Wind slabs typically form just below exposed ridgelines and within gully walls (cross-loading). Use visual clues to determine where slabs may still lurk downslope, such as textured/uneven surfaces and recently formed drifts/cornices. At this point, it's unlikely you'll get clear signs of instability, such as shooting cracks, blowing snow, or recent slab avalanches. You can reduce your risk by choosing smaller slopes with less exposed hazards below, or avoid this problem entirely by steering around exposed, wind-affected slopes steeper than 35 degrees. Give overhanging masses of snow a wider berth, both from above and below.

    (4/15/2026)

    Standing at the top of a small (D1.5) skier triggered wind slab avalanche in the Teanaway. Avg crown depth was 6-8in and the slide propagated about 200 ft wide.

    SS-ASc-R3-D1.5-S

    Photo: Payton Schiff

Avalanche Discussion

The last avalanche forecast for the 25-26 season will be for Sunday, April 19th. Mountain weather forecasts will be published each afternoon through May 3rd. A huge thanks to everyone in our community for your support this winter!

Earlier in the week, the western parts of East South picked up 9-12 inches of new snow according to telemetry data, accompanied by strong wind from the west. Areas to the east were largely rain-shadowed throughout the week, minimizing precipitation and subsequent avalanche hazard. An NWAC forecaster traveling in East Central on Wednesday triggered several small wind slab avalanches that failed on mid-storm interfaces and one that notably broke on the 4/14 crust about 12 inches deep. They also observed natural wind slab avalanches triggered by cornice fall. All triggered and natural avalanches were on E aspects between 6-6500f ft. They also noted blowing snow and sunbreaks that would stiffen the surface snow on sunny slopes. An avalanche professional traveling in East Central on Thursday noted continued wind transport at ridgelines. We suspect similar conditions have existed in East South.

The recent snow has been followed by increasing sunshine and warmth each day. This "slow bake" of the snowpack has left a lot of questions in its wake regarding instability going into Saturday. Whatever outing you have planned, be sure to have an exit strategy that keeps you out of avalanche terrain where warmed, weakened snow may fall. This includes terrain where wind-affected snow influenced by warming can fail. Don't get yourself backed into a corner by having to descend a hot, south facing slope at 4:00 in the afternoon, for example. There are plenty of exposed hazards in the terrain right now, thanks to our meager winter, so consider the consequences of getting caught up in even a small avalanche.

The prolonged warm spell in March decimated the already struggling East South snowpack. Below 5,000 ft, snow coverage is too limited for avalanche danger at this time—so we’re issuing a No Rating for lower elevations. You can still find rideable snow at middle and upper elevations.

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