Bulletin d’avalanche

West Slopes South

Northwest Avalanche Center
Voir sur la carte

Danger d’avalanche

Sat
Alpin
2 · Modéré
Limite forestière
2 · Modéré
Sous la limite
2 · Modéré
Open full map
Périmé — ce bulletin a expiré 5 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

Another day of warm and sunny weather will help weaken the snow surface and increase the likelihood for you to trigger loose wet avalanches. When you begin to find wet and punchy snow or see fresh teardrop-shaped slides, seek out firmer or lower angled terrain.

Problèmes avalancheux

  • Loose Wet

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1–2

    Another warm and sunny day will quickly soften any crust that develops overnight. As the surface weakens you may trigger loose wet avalanches on steep slopes over 35 degrees. When you begin to sink into the snow past your ankle or you see snow naturally rolling downhill, it’s time to change locations. Find more frozen or lower angled terrain to stay ahead of the loose wet hazard. Easterly slopes will soften quickly in the morning before wet snow spreads to other aspects and onto the northern half of the compass dial. Anticipate this rapid change and plan to travel early before unstable snow becomes more widespread. Later in the day, you could see natural wet avalanches as water impacts more of the upper snowpack. With the current conditions, these slides could entrain snow, grow large, and travel far downslope.

    (4/15/2021) When you find a wet, sticky, and punchy snow surface like this you may trigger loose wet avalanches on similar slopes. New rollerballs are also present on the slope.

Avalanche Discussion

While the West-South zone has experienced warm temperatures recently, moderate to strong easterly winds have helped limit the pooling of water at the snow surface. Windy weather again on Friday should continue to help keep the snowpack cool and the avalanche danger slightly lower than zones to the north. However, locations on Mt Rainier and Mt St Helens experienced less wind and warmer overnight temperatures. Consequently, you could encounter locally more dangerous conditions in these areas with larger and more abundant natural avalanches. 

Predicting the timing of these spring-time avalanche cycles is tricky. While you could see natural avalanches Friday, we don’t think this will be the day for more widespread activity. Pay attention to the terrain above you. Choose routes that reduce the amount of time you spend below rocky faces, slopes with crevasse-like glide cracks, and overhanging cornices. As temperatures warm up, snow tends to fall down. Make sure your travel plans leave you with plenty of options to reduce your exposure and change plans if you begin to see more natural avalanche activity than expected. 

Daily avalanche forecasts will end on Sunday, April 18th.

During the ongoing Covid-19 pandemic, continue to follow the latest guidance from local, state, and federal health officials. Avoid unnecessary risks that could impact first responders and stress medical resources.  Wear a mask when appropriate, practice social distancing, and consider recreating closer to home.

Régions couvertes