Avalanche forecast

Olympics

Northwest Avalanche Center
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Avalanche danger

Sun
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
No rating
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Highlights

You can trigger slabs within or just below 6-10" of low-density new snow. Most slabs will be small, releasing from steep or unsupported slopes.  Smooth-looking and rideable lee start zones may harbor drifts large enough to bury you in a gully or rake you through dangerous early-season obstacles.

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    Hurricane Ridge is expecting the largest snowfall since December 1-2, with most of this 6-10" arriving Friday night. Moderate winds, particularly Friday evening will redistribute that snow, with less wind-affected snow on top. This will serve to cover up the pillow-like drifts where a slab will have the cohesion for propagation across a slope. Conditions could be dangerous to start the day if we get closer to 10" of snow.  We also have uncertainty surrounding how a rime crust / facet / melt-freeze crust combo buried 1/5 will react to the fresh load. While we're not expecting large avalanches, anything triggered at the top of or within the aforementioned crust complex may surprise you and could bury you in a gully, or creek, or rake you into shallowly submerged objects. Ease into the terrain with an extra degree of caution for a "moderate" danger day. Note how well the snow bonds to the rime crust. Try to initiate failure within the crust-facet complex on representative test slopes before entering slopes steeper than 35 degrees, unsupported slopes that roll steeply below you, or wind-loaded start zones. Warning signs including shooting cracks, whumphs (settlement of the crust-facet combo), and recent avalanche activity all suggest that you consider reducing your terrain selection further.

    Example: This Intentionally triggered size 1.5 avalanche from earlier this season is about as large as a slab would be on Saturday. Such an avalanche would release in a wind-loaded start zone like this one. 

    Photo: NPS Rangers

Avalanche Discussion

The snowstorm Friday night brings winter back to Hurricane Ridge after an abysmal start to the season, but it also brings real avalanche danger and a sharp shift from the recent lack of avalanche problems.  But don't forget about the shallowly submerged (and now invisible) early-season hazards that lunk inches below the surface on most aspects.

Human psychology can play strange games with us. When something is in short supply (such as powder snow), people tend to rush at the opportunity presented when it arrives. This is the exact opposite behavior for a day when your mindset should be stepping back and off of terrain that you recently traveled freely on. Fight against these human factors, particularly when you can anticipate them and take the extra time to evaluate whether conditions are in line with or differ from the forecast.

Hurricane Ridge was tied for its lowest snowpack in our record for the station as of January 1st. Currently, 17" of snow sits on the ridge proper with around 2" of accumulation as the storm ramped up Friday afternoon with winds increasing into the moderate range.  Prior to the storm, a lot of variability in snow depth existed by aspect, but the only rideable snow is on the northern half of the compass above around 4500 ft. The most recent atmospheric river (late December) was buried on January 2nd by low-density snow. About 3/4 inch of low-density snow sits atop the crust and is capped by 1/4" of rime on all aspects at Hurricane Ridge elevation. The 2" of fresh snow has redistributed atop the rime crust, with more expected to be added throughout the night and perhaps an inch or so added during the day Saturday. 

On 12/30, a public observation from Mt Townsend found a dusting of snow at the summit, snow depths of less than 2' in a wind-loaded NE gully, and little snow below 5200' in general. Observers were out in the Hurricane Ridge area on Friday, traveling on foot on southerly aspects so they could access northerly aspects where there was enough snow coverage to link turns.  Thanks to the sustained mild temperatures, they found enjoyable and spring-like conditions at the end of December.   In Klahane Bowl on northerly aspects,  roughly 1.5-2" of snow sits over the latest crust.  There were numerous rollerballs and point releases visible from the recent warm and occasionally rainy weather.  No new avalanches or layers of concern were observed.  

NWAC may issue a gray "No Rating" for an elevation band when there is not enough snow to present an avalanche hazard.

Regions covered