Bulletin d’avalanche

Presidential Range

Mount Washington Avalanche Center
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Danger d’avalanche

Tue
Alpin
1 · Faible
Limite forestière
1 · Faible
Sous la limite
1 · Faible
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Périmé — ce bulletin a expiré 5 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

Firm snow that is generally stable is common in avalanche terrain today. Watch out for changes in snow hardness and isolated areas where snow becomes soft and easy to step into, as this could be a sign of instability.

Problèmes avalancheux

  • Wind Slabs

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

    Small wind slabs exist in starting zones, high up in the terrain in sheltered and wind-protected areas. Slabs are between 6 inches and 2 feet thick and are highly variable in size, distribution, and hardness. Careful assessment of softer snow is advised, especially above consequential terrain or terrain traps. These slabs are unlikely to avalanche naturally, but small, human-triggered avalanches are not out of the question for those pushing into big terrain to find the softest snow.

Avalanche Discussion

A few days of warm weather and some sunshine has helped grain and layer bonding within the snowpack. Steep solar aspects in the higher elevations and low-elevation snow warmed enough to melt surface snow and subsequently create a crust as the temperatures dropped over the last day. This melt freeze crust will create a slick, frozen surface on many south-facing slopes which is worth remembering for the next snowfall, as it will likely become a low-friction bed surface for future avalanche activity. At the lower elevations, expect a crust to be tough to travel on and create a hard-over-soft layer right at the surface of the snowpack. 

The forecasting team has been talking about the formation of small cornices at ridgelines where there is a transition to steep, north-facing terrain. We don’t often see cornice formation in the local terrain and this circumstance is indicative of unique wind-loading conditions on a south or southwest wind, which happened on February 4th and February 7th. These overhangs have created even more sheltered terrain for soft snow to collect below and form small slabs. Though interesting, they are not large enough to warrant the addition of a Cornice avalanche problem or be concerned about natural cornice release. 

The Lion Head Summer Trail is now closed for the season due to avalanche risk. The Lion Head Winter Route is open.

Please help us and your fellow skiers, riders, and climbers by submitting any pertinent or interesting observations to our website. 

Régions couvertes