Bulletin d’avalanche

Snoqualmie Pass

Northwest Avalanche Center
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Danger d’avalanche

Thu
Alpin
2 · Modéré
Limite forestière
1 · Faible
Sous la limite
1 · Faible
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Périmé — ce bulletin a expiré 2 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

Happy Winter!

You may still trigger a small avalanche on steep and exposed slopes near ridge lines. You can stay safer by steering clear of steep wind-loaded terrain above 5000 feet. Remember that it's early season and hidden obstacles could increase the consequences of being caught in a slide. 

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1–1.5

    Winds drifted the recent snow into thicker slabs where you could still trigger an avalanche on Wednesday. The greatest hazard exists at upper elevations, especially on steep and exposed slopes below ridgelines. In complex terrain such as gullies, couloirs, and below cliff bands and sharp ridgelines, you may find thicker, deeper, and more dangerous drifts.

    Before committing to steep terrain, look for signs of wind-drifted snow, such as textured surfaces, cornices, rime, and chalky, pillow-like drifts (see photo). Use small test slopes, uptrack tests, and hand pits to identify wind slabs and assess their bond to the surface below. With cool, calm weather and fresh snow, you’ll find safe and enjoyable riding conditions outside of wind-affected zones.

    (2/22/2024)

    An example of visual clues of wind loading along ridgelines. These signs help us anticipate where wind slabs may exist. 

    Photo: Dallas Glass

Avalanche Discussion

Welcome to the 2024-2025 Forecasting Season!

It's early season and limited observations leave us uncertain about the extent of wind loading at the upper elevations and how reactive any wind slabs might be. On Monday, Alpental Pro Patrol noted moderate scouring and drifting from Sunday's storm near the Denny Summit. If you venture into complex terrain on Tuesday, you could still encounter a lingering wind slab. Remember that big terrain can bring big consequences, regardless of the size of the avalanche. 

Here's the good news:

  • It's been a few days since the last snowfall, winds have been light to moderate, and snow totals were only about 6". These factors should help temper both the reactivity and size of any potential wind slabs.
  • On Tuesday, Alpental Pro Patrol reported moist snow with no obvious signs of instabilty at 4500' on a NE aspect. Relative warmth and a bit of moisture should help to settle the snow and promote bonding of any potential wind slabs to the surface below.
  • Early season riding conditions are rather good above 5000 feet, especially on the northern half of the compass.

With calm weather on the horizon, there’s no need to rush into committing terrain tomorrow. Consider giving the snowpack another day to adjust to the recent load.

Early Season Hazards

Coverage is great for late November, with snow depths up to 5’ at 5000’. However, lower elevations remain thin, with exposed creeks, rocks, stumps, and brush making travel into and out of the quality snow zone challenging and hazardous.

If you get out into the mountains, please submit your observations to help us improve the forecast for all our backcountry community.  Here's to a great 2024-2025 season!

Uphill Travel 

Uphill travel at a closed ski resort: 1. Follow the ski area’s uphill travel policy. 2. Avalanche mitigation may not have occurred. You should approach the terrain as if it were any other backcountry slope. 3. Numerous other hazards may exist, including electrical lines, snowmaking, heavy machinery, and other motorized traffic. 4. Ski patrol and other ski area staff are not there to respond to emergencies. Travelers should be self-sufficient.

Régions couvertes