Bollettino valanghe

Presidential Range

Mount Washington Avalanche Center
Vedi sulla mappa

Pericolo valanghe

Sat
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
Senza grado
Open full map
Non aggiornato — questo bollettino è scaduto 2 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Avalanche conditions remain dangerous. Today, avalanches could happen naturally or by human triggers and could be large enough to bury you, multiple people, and damage trees. These dangerous avalanche conditions can be found on all aspects, with the largest on west-facing slopes. Deep drifts of new snow or cracking underneath your feet are signs that conditions are unstable. Today, use conservative decision-making to mitigate hazards today and approach avalanche terrain cautiously.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1–2.5

    Avalanche conditions remain dangerous, with wind slabs being a concern across all aspects at middle and upper elevations. The largest wind slabs will likely be found on west-facing terrain, and these wind slabs may avalanche naturally or be sensitive to the weight of a person. These avalanches could be multiple feet thick and have the destructive potential to bury multiple people and destroy a few trees. Visual assessments will be critical today, and with overcast skies, fog, and new snow, this may not be possible.

    Signs of dangerous wind slab conditions will include smooth, rounded, and pillowy snow slopes, deeper drifts in wind-protected areas, shooting cracks under your feet, and recent avalanches. Assessing slab depth will help understand the size of these newly formed wind slabs, and instability tests like hand shears and column tests will help understand sensitivity. Manage your overhead hazard by limiting time underneath large wind slabs and traveling one at a time across avalanche terrain. Consider the terrain and potential consequences today as decision-makers; these avalanches have the potential to be large and may not give many warning signs of instability.

Avalanche Discussion

This storm has been interesting to track, as it brought less snow and higher wind speeds than forecast. There is some uncertainty about the size of wind slabs, which will make visual assessments critical for decision-making. The terrain may limit the potential size of avalanches, but the terrain is highly consequential and small avalanches in these terrain traps have been deadly. Today, there is the possibility that you could be dealing with large avalanches that may be unsurvivable. 

The combination of cold temperatures and an icy bed surface makes these slabs more reactive, as they are less likely to bond to the slick surface. Additional snowfall today will add to the size of slabs and the changing winds will distribute more snow, but the biggest and most concerning impact from this snow will be limiting visibility. 

Today’s decreasing hazard does not indicate stable conditions. These are newly formed wind slabs, and today human triggered avalanches are likely and naturals are possible. Assess consequences and terrain critically today as the spatial variability may limit the value of instability assessments like column tests and hand shears. 

OBSERVATIONS: Please consider submitting an observation of what you are seeing in your travels. Submitting an observation hones your skills, informs other users, and improves our forecasts. 

Help avalanche researchers! The Colorado Avalanche Information Center, the Avalanche Research Program at Simon Fraser University, and the U.S. National Science Foundation National Center for Atmospheric Research are researching how skiers, snowmobilers, snowshoers, ice climbers, and anyone else who travels in the backcountry interpret avalanche forecast information. Completing this survey will take approximately 20 minutes. Thank you!

Regioni coperte