Bollettino valanghe

Presidential Range

Mount Washington Avalanche Center
Vedi sulla mappa

Pericolo valanghe

Fri
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
1 · Debole
Open full map
Non aggiornato — questo bollettino è scaduto last year. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Wet snow avalanches are possible as without an overnight refreeze, snow on steep slopes above 3000 feet remains unstable. Limit your time underneath steep slopes as naturally occurring avalanches should be on your radar today. 

Problemi valanghivi

  • Wet Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2

    What and where is it:

    1.18 inches of rain and above freezing temperatures at middle and upper elevations have warmed and wetted the snowpack. Newer and softer surface slabs may have lost some of their structure, but firm snow surfaces may have only softened. Many observations from the past week have referenced poor, strong-over-weak structure on a firm pencil hard surface below that could slide today.

    How can you recognize it: 

    Any snow on a steep slope should be treated as an area that could slide today. Assessing the snow structure will let you know if you have more of a wet slab (if there is structure) or wet loose (finding structureless gloopy snow) problem on the snow you are in. A red flag for today is periods of continued heavy rain as this will add additional weight to the snowpack.

    How can you manage it:

    Approach today with a head’s up mindset. Identify steep, convex features that may be areas more likely to slide and limit your time underneath them. The snowpack may give limited warning signs and wet snow while slow, has dense, heavy, and destructive debris. There is no good way to assess structure, stability, and how much water has entered the snowpack without digging into the snow, and you will incur exposure to do this.

Avalanche Discussion

Without an overnight refreeze, the snowpack has not yet had time to settle so if you choose to enter avalanche terrain today, treat snow as unstable. While the surface may feel like spring snow, do not underestimate the structure beneath your feet. In the spring the snowpack becomes uniform in structure, temperature, and is stable. This is still a winter snowpack with variable structure, and interfaces that could still be conducive to wet snow avalanches.

There are unknowns today as wet snow avalanches are unpredictable and challenging to forecast. It is possible that rain and warming have created settlement and you will just be contending with loose wet snow surfaces as problems today. On the other hand, firmer slabs may have needed time to sufficiently soften and for water to percolate through the snowpack. For all of these reasons, approach today actively assessing conditions. The steeper slopes are likely to hold the most unstable snow so choosing less steep terrain is one way to manage the hazard today.

Looking ahead, this evening temperatures are forecast to slowly drop below freezing and precipitation will change to snow. At this time shift your attention to the new snow and wind as this combination may create new surface avalanche problems in easterly aspects. This widespread refrozen surface will also create slide-for-life conditions on Friday and Saturday. These conditions can be some of the most dangerous in the Presidential Range, responsible for too many injuries and fatalities

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.

Regioni coperte