Bollettino valanghe

West Slopes Central

Northwest Avalanche Center
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Pericolo valanghe

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3 · Marcato
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3 · Marcato
Sotto il limite
2 · Moderato
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In sintesi

Big changes are coming, with increasing temperatres and precipitation, so this is a time to travel carefully in the backcountry. Wet avalanches will impact all the way to upper elevations by the afternoon on Sunday, so steer clear of steep slopes where wet avalanches start, run and stop. If you make it to upper elevations, avoid steep slopes, except for where surfaces have been swept back to crusts. 

Problemi valanghivi

  • Loose Wet

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    • Limite del bosco
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    Probabilità
    Likely
    Dimensione
    1–2

    Wet avalanches will happen in areas with previously light, dry snow. Expect initial peak activity Saturday night, but as temperatures creep higher on Sunday, avalanche activity will shift up the mountainside with the rising snowline. 

    Wet avalanches frequently occur naturally in the presence of rain. At least they tend to be predictable- there are usually several that happen in close proximity or similar timing. If you see one, expect similar avalanches to happen nearby. Avoid steep terrain, where you could initiate a slide in wet snow if you're sinking in more than a few inches. Also, steer around lower-angle areas beneath a steep slope, where these wet avalanches could run and stop. 

    These avalanches also frequently initiate in gullies, from tree bombs, or near rocks. They may fan out extensively from there. It's hard to tell, but this might be a day where you need to take wet avalanches more seriously than you might normally- sticking to more conservative terrain is a good plan for this wet, warm day. 

    Example photo: Wet loose avalanches, like ones that might occur on Sunday. Avoid steep areas and the runout beneath steep slopes if there's wet snow you're sinking into or avalanches happening nearby.  

  • Storm Slabs

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    • Limite del bosco
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    Probabilità
    Likely
    Dimensione
    1–2

    The challenging weather will probably keep most people away from upper elevations. But if you make it up there, expect to find reactive slabs. Many upper elevation areas will likely be wind-affected. Expect larger and more reactive slabs in these areas. Even in sheltered areas though, increasing temperatures will form "upside down" layers near the surface, so you could trigger an avalanche here, too. 

    Avoid all steep slopes where either heavier wind-drifted snow or lighter, non wind-affected snow exists. If you must be out on steeps, wind-stripped areas where there is a harder crust are the place to be - but consider having crampons if you venture out there!

    Example photo: You can trigger slab avalanches even on non wind-loaded slopes, but expect them to be larger and more reactive in wind loaded areas. 

Avalanche Discussion

On Friday, January 9th, four backcountry skiers were caught and carried by a large avalanche while descending near Longs Pass in the Teanaway River drainage. The slide occurred on a S to SE facing slope at approximately 6200ft. One member of the party was not buried. Another teammate was partially buried but injured. The other two individuals were fully buried. During the initial rescue, the team located one of the buried victims, who did not survive. Despite the group's best efforts, they could not pinpoint the fourth member of their team. The party contacted 911 via a satellite device, and Kittitas County Search and Rescue responded to the area on Friday evening. Additional rescue efforts were postponed until daylight. Search and Rescue then returned to the site on Saturday and were joined by NWAC forecasters. The teams were able to locate the remaining victim. Unfortunately, neither of the fully buried skiers survived. Our deepest condolences to the family, friends, and community of those involved in this avalanche accident. S-SE aspect, 6200ft, Avg Depth 2ft, HS-AS-R3-D2.5-O

I was out in the West Central zone on Saturday. South-facing slopes, and even flat surfaces at lower elevations were crusty or moist. I reached over 5000ft, and was surprised that steep south faces, even at that elevation, were crusty. Avalanche concerns were minimal thanks to the crust. As soon as I shifted around the corner, I saw enough loading that I veered away from the steep slopes in front of me, as I was concerned about triggering an avalanche on a wind slab. Non wind-loaded terrain was stable. You can check out my observation HERE. 

Forecasts are calling for just under half an inch of water Saturday night, with snowlines at about 5500ft. We'll get just under an inch of water during the day, with snowlines rising to 7000ft. Plus wind. There's even more water and higher snowlines in the forecast for Monday. 

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