Bulletin d’avalanche

Central Sierra Nevada

Sierra Avalanche Center
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Danger d’avalanche

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

Points saillants

New snow combined with gale force winds will have drifted snow into cohesive slabs along the downwind side of ridge features and into gullies. Loose snow avalanches are expected today in wind protected areas with the character changing from dry snow to wet snow in some areas as the day progresses. Consider avoiding avalanche terrain in areas where signs of unstable snow exist.

Problèmes avalancheux

  • Wind Slabs

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

    Blowing and drifting of old and new snow occurred over the past 24 hours as SW winds increased to gale force. Fresh slabs of wind drifted snow were deposited along the downwind side of ridge features and into gullies. Use clues such as recent avalanches, snow surface cracking, cornices, snow drifts, and snow surface texture to identify potentially unstable slopes and consider avoiding them.

    (3/27/2024)

    Drifting snow was more than expected yesterday prior to the onset of snowfall. Blowing and drifting snow moving left to right over the ridgetop is visible in this photo. Castle Pk to Basin Pk ridgeline, Donner Summit area, CA

    Photo: Sierra Avalanche Center

  • Loose Dry

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

    The new snow from last night at 4 to 9 inches is expected to undergo changes from dynamic spring weather conditions today. Most wind protected areas are expected to start out with mainly a dry loose problem this morning. Storm slab conditions may exist in some areas that received the upper end of new snowfall amounts. As daytime warming progresses, strong sunshine may change the avalanche character more towards a wet loose problem. Expect dynamic avalanche conditions that may change rapidly from one lap to another or from one location to another as you move through the backcountry today.

    Look for signs of unstable snow for multiple types of avalanche problems and reevaluate conditions as the day progresses. Dry sluffs are indicative of a dry loose problem. Rollerballs and pinwheels are indicative of a wet loose problem. Snow surface cracking and slab failure on test slopes in wind protected areas are indicative of a storm slab problem. Enter the backcountry with a flexible travel plan that provides terrain options. Adapt specific terrain selection (aspect, slope angle) for the conditions you encounter.

Régions couvertes