Bulletin d’avalanche

Presidential Range

Mount Washington Avalanche Center
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Danger d’avalanche

Sun
Alpin
1 · Faible
Limite forestière
2 · Modéré
Sous la limite
1 · Faible
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Périmé — ce bulletin a expiré 8 months ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

You could find small areas of unstable wind-drifted snow on steep, east-facing slopes where the terrain has provided protection from the wind. Be cautious around deeper drifts of snow that appear bright white and smooth in contrast to the hard, textured old snow.

Problèmes avalancheux

  • Wind Slabs

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

    What and where is it:  Between December 23rd and 25th, about 11 inches of new snow fell and, as westerly winds increased, wind slabs formed on east-facing aspects, many of which avalanched naturally late on the 25th and 26th. Since then, many hours of strong west winds have scoured upper and middle elevations, stripping snow from exposed terrain and leaving surfaces firm or hard, improving overall stability. In wind-sheltered terrain, pockets of drifted snow remain, and isolated wind slabs may still be reactive to a human trigger.How can you recognize it: Look for areas of deeper snow drifts that are smooth, rounded, and have been protected by recent high winds to spot this lingering avalanche problem. Find a safe area to dig down into the snowpack to assess the presence of a weak layer and evaluate the sensitivity.How can you manage it: Use travel techniques that minimize your time spent exposed to large, open snow slopes. While triggering an avalanche today could be difficult due to a firm snow surface, however finding an invisible thin spot in the snowpack could be the trigger for a consequential avalanche.

    (12/26/2025) - Stong over weak snowpack in Tuckerman Ravine. 

Avalanche Discussion

Multiple observations from yesterday indicate that many east-facing avalanche paths experienced a natural avalanche cycle following recent snowfall and a prolonged period of strong westerly winds. (OBS1, OBS2, OBS3, OBS4) These avalanches were consistent with expectations given the amount of low-density snow available for transport and the intensity of wind loading during that period.

Since then, continued strong winds have had a stabilizing effect. Forecasters yesterday confirmed that exposed terrain has been significantly hardened and scoured. However, areas with strong-over-weak structure still exist that are capable of sliding should a human find the weak spot in the slab. Low Elevations: Concerns at elevations below 3,000 feet remain limited. Overall, avalanche conditions are generally safe at these elevations because the snowpack is still relatively thin and discontinuous. That said, small pockets of drifted snow can exist where terrain concentrates loading, so watch for isolated, steep snow covered slopes or gully features where snow has collected.

Looking ahead, a storm Sunday night into Monday may introduce new stability concerns. We still need better resolution on precipitation type by elevation, but at this point it appears likely that freezing rain and possibly rain will impact the existing snowpack. Tomorrow’s forecast will address these concerns as confidence improves in snow levels and precipitation types.

OBSERVATIONS: Please consider submitting an observation on our website or in the new Avy phone app of what you are seeing in your travels. Submitting an observation hones your skills, informs other users, and improves our forecasts. 

Régions couvertes