Avalanche forecast

East Slopes South

Northwest Avalanche Center
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Avalanche danger

Wed
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
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Highlights

New snow and wind will create dangerous avalanche conditions near and above treeline. Tuesday will be a good day to take a step back and avoid slopes that show signs of fresh wind loading. 

 

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2

     New snowfall and radical wind speeds will build large slabs of wind-drifted snow near and above treeline. These may be easily triggered by the weight of a human, so you’ll want to give these areas a wide buffer.

    Due to high wind speeds, you may find these slabs forming in unusual areas, such as well below treeline and further down slope than usual. You’ll also find them forming under cornices, on the leeward side of ridges, and scattered through the alpine. However, it won’t be the day to search these things out. Use visual clues to help you avoid slopes of concern. Look for where the wind is blowing snow, sharp cornices forming, or pockets that look rounded or pillow-like. These are all indicators of wind slabs forming near-by. If you notice shooting cracks, take a big step back and avoid any nearby steep terrain. 

    (12/3/2022)

    Actively blowing snow, freshly building sharp cornices, and textured surfaces. All easy-to-identify signs of wind-loading. Look for slabs to develop on the slopes on the left side of the picture.

    Photo: Dallas Glass

Avalanche Discussion

Avalanche Accident Colchuck Pk, East Central Zone

We’ve received preliminary information of an avalanche incident on Colchuck Peak, SW of Leavenworth, WA. (East Central Zone) The accident occurred on Sunday, February 19 and involved a group of 6 backcountry travelers. Three members of the group are suspected to have been buried and perished in the event. Another sustained injuries and was evacuated by SAR.  Rescue efforts are ongoing. NWAC is working with Chelan County Sheriff’s office and will make updates as more information becomes available.

 Forecast Discussion:

This should be a pretty good storm for the east-south. Darland Mtn is forecasted to get just under 1” of precipitation paired with strong west winds. With this, we’ll see a sharp uptick in avalanche danger, specifically in those wind loaded areas. However, you should keep your eye out for other instabilities as well, such as storm slabs  or even loose wet avalanches if the sun makes an appearance. 

The key message here is that subtle differences in precipitation totals, sun, or wind can heavily influence the avalanche dragon you’re dealing with. So your best tactic will be to be observant and carefully evaluate each slope. 

As we move into this stormier regime the big question mark will be how the new load bonds with the old snow surface. Observers have reported weak, faceting snow on northerly aspects.  So as new snow piles up, be sure to check how its bonding with the old snow interface. Use small test slopes or hand pits to gauge how easily the snow slides. 

On Friday an observer in the American Ridge area reported finding good cold snow on east facing terrain, faceting snow in the shade,  and a sun crust on solar slopes that extended up to ridgetop.  At higher elevations they noticed winds drifting any remaining soft snow. Check out their full observation here. 

Let us know what you see by submitting a public observation. 

 

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