Issued: 6:00 PM PST Sunday, December 31, 2017
by Kenny Kramer

Keep an eye out for signs of wind transported snow such as fresh cornices, uneven snow surfaces, and wind drifts. Avoid areas of wind deposited snow, especially above treeline where more soft snow is available for transport.

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  • No Rating— (Info Avail)
  • Low — 1
  • Moderate — 2
  • Considerable — 3
  • High — 4
  • Extreme — 5

Avalanche Problems for Monday

Wind Slabi

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Persistent Slabi

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Forecast for Monday:

The New Year will kick off with another day of mild weather in the Olympics. Mostly sunny skies and warm temperatures will create yet another day for the snowpack to gain strength.

Watch for lingering wind slabs in exposed terrain, especially above treeline. Look for signs of wind transported snow such as uneven snow surfaces, fresh cornices, and snow drifts. Each of these observations are signs that the wind has redistributed snow in the area. Identify and avoid wind loaded terrain features.

Wind slabs can be deceptively difficult to manage in the terrain. Take a moment and read our recent blog post by NWAC Pro Observer Jeremy Allyn on wind slabs.


Avalanche Summary:

Happy New Year from your friends at NWAC!

Mild weather Sunday allowed the snowpack to continue to heal and gain strength following an active weather pattern this past week.

SW winds Friday night redistributed new snow forming shallow wind slabs on lee slopes at higher elevations. This resulted in a variety of snow surfaces including soft unconsolidated snow, wind scoured slopes, rain crust, and firm wind slabs.

Friday’s warm weather resulted in a rain crust at most elevations. Limited information has been received about the extent, supportability, and bonding of new snow to this crust.

The 12/16 mid-December crust can still be found 2-3feet down within the snowpack.


NWAC pro observer, Matt Schonwald visited Hurricane Ridge on Friday, 12/29 and stressed that this is a different snowpack than the Cascades! He visited W-NW-N-NE aspects and found the 12/16 crust and 1-2 mm facets down 2.5 feet. Several PST tests failures, self-arrested, but propagated through most of the column along the 12/16 layer. This indicates that a persistent slab layer could be triggered most likely on large convex slopes below the ridgelines.

No Corresponding Mountain Weather Forecast Available


NWAC avalanche forecasts apply to backcountry avalanche terrain in the Olympics, Washington Cascades and Mt Hood area. These forecasts do not apply to developed ski areas, avalanche terrain affecting highways and higher terrain on the volcanic peaks above the Cascade crest level.