Bulletin d’avalanche

Central Sierra Nevada

Sierra Avalanche Center
Voir sur la carte

Danger d’avalanche

Alpin
2 · Modéré
Limite forestière
2 · Modéré
Sous la limite
2 · Modéré
Open full map
Périmé — ce bulletin a expiré 7 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

MODERATE avalanche danger exists at all elevations today mainly due to loose wet avalanche problems. An unlikely but not impossible wind slab problem may still linger in some isolated places as well.

Problèmes avalancheux

  • Loose Wet

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

    Warmer temperatures, strong sunshine, and less wind should allow enough warming for loose wet avalanches to become possible today. These could be small or large enough to have more serious consequences for backcountry travelers. Larger loose wet avalanches could occur on long, steep, sun-exposed slopes. Any size loose wet avalanche could be problematic in areas where terrain traps magnify its severity. As more daytime warming occurs, this problem will become more widespread. 

    Wet surface snow, pinwheels, and roller balls can foreshadow larger loose wet avalanches. Moving to more shaded and sheltered northerly aspects can help find colder soft snow and reduce exposure to avalanche concerns.

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely
    Taille
    1

    Triggering a wind slab avalanche has become unlikely in the majority of areas. Unlikely does not mean impossible. A surprise wind slab failure cannot be ruled out in some isolated locations especially in complex or extreme terrain including couloirs, cliffy areas, unsupported slopes, and steep convex rollovers. Larger triggers like large cornice failures may also still be able to release an avalanche.

    Variable, challenging, firm, wind affected snow conditions will exist in areas where difficult to trigger wind slabs may still linger. Avoiding these less fun snow conditions in favor of the softer snow that should still remain in more sheltered terrain could provide more enjoyable recreation and help avoid potentially unpleasant wind slab surprises.

Avalanche Discussion

* Yesterday observations from the Incline Lake Peak area revealed firm wind slabs on multiple aspects. Tests on the newer wind slabs still yielded some unstable results. Tests on the older wind slabs did not show signs of instability. All observations indicated that these wind slabs are becoming more difficult to trigger.

* In sheltered areas no signs of instability existed. Cold soft snow still lingered on northerly aspects. On sun-exposed southerly and easterly aspects heavier snow existed above older sun crusts by mid-afternoon but no wet snow instabilities were observed.

* A natural avalanche occurred on Jobs Sister. It was seen from a distance and details about its size, trigger, and type remain uncertain. It may have been triggered by rockfall. 

Régions couvertes