Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

Fri
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Highlights

Keep an eye out for wind-loaded features where triggering an avalanche is more likely on Thursday. While some of these slabs may be easy to spot, others may be hidden under a bit of new snow. Take the time to evaluate a slope carefully before you commit yourself.

Avalanche problems

  • Wind Slabs

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

    The most likely location for you to trigger an avalanche on Thursday will be in wind-loaded terrain. Some Wind Slabs may be buried under freshly fallen snow, hiding from view. So you should try to feel for subtle changes in the snow’s stiffness to help identify where they're lurking. Using other visual clues such as freshly built cornices or new drifts behind objects can help you identify which way the wind was blowing. The wind often likes to deposit snow at the base of cliffs, the side of gullies, or on convex features. And of course, the leeward side of ridgelines is an obvious place to find wind-loaded slopes. Now that you know what to feel for and where they’re more likely, you can start to identify wind-loaded features to avoid.

Avalanche Discussion

Winter recreationalists, rejoice. There was fresh snow to play in around the West South on Wednesday. That said, the winds, particularly in the southern part of the zone, probably blew a lot of it away. Observations from the day were a bit limited, but NWAC forecasters near Crystal Mountain found swirling winds, at least one fresh natural avalanche (D2), and some sensitive cornices. As we look toward Thursday, more snow showers are on the way but the winds should decrease some. That doesn’t mean snow won’t be blowing around, particularly in the more wind-prone areas or the southern half of the zone. If you find that the snow has piled up deeper than you expected, you could experience locally higher avalanche hazard. If this happens, take a step back and start to question all slopes over 35 degrees.

Thursday’s accumulation will combine with Wednesday’s to thicken the amount of dry snow over the Christmas Crust. This sturdy snowpack marker was found on all aspects but varied in burial depth and thickness as described by NWAC forecasters on Wednesday. The culprit for creating this crust is, of course, the significant rainfall throughout our zone since 12/23. This deluge resulted in a Wet Slab avalanche cycle, with multiple very large avalanches triggered by Crystal Mountain Ski Patrol on 12/26. We have pulled the official Wet Slab problem from our forecast, but will keep thinking and talking about it until we get some confirmation that the weak and wet snow under the Christmas Crust has started to freeze and stabilize. Wet avalanches can often occur long after the rain has stopped, and the cooldown we are currently experiencing is slow and methodical, delaying the freezing process.

As we slowly make our way out of this stormy and active period, you could find some unusual conditions or difficult travel in places. We’d like to hear about them or anything else you’re seeing out there. So please submit a public observation.

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