Bollettino valanghe

Presidential Range

Mount Washington Avalanche Center
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Pericolo valanghe

Sun
Alta quota
1 · Debole
Limite del bosco
1 · Debole
Sotto il limite
Senza grado
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In sintesi

Avalanches are unlikely for the first half of the day. If temperatures cool enough in the afternoon, watch out for wind drifted snow above 4000 feet building deep enough to avalanche. Evaluate new snow deeper than your boot top.

* If we recieve the upper end of possible accumulating snow, drifted slabs of snow will be larger and may push the hazard rating towards MODERATE late in the day. 

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–1.5

    Small, stubborn wind slabs may form high in the terrain later this afternoon when temperatures cool and snow accumulates.  

    The Mount Washington wind slab machine has around 0.5 inches of liquid precipitation available during daylight hours. Warm temperatures are likely to keep this precipitation as more rain than snow nearly up to the summit. When temperatures cool in the afternoon, the chance for accumulating snow increases as wind shifts west. Up to 5 inches of snow is possible on the higher summits before the sun sets, enough snow to create small, stubborn wind slabs high up in the terrain. 

    Monitor temperatures throughout the day; a shift warmer or cooler will directly influence accumulating snow.  

Avalanche Discussion

Mixed precipitation types and temperatures hovering just above and just below freezing add uncertainty to today’s forecast. 

What we do know: 

  • We are starting the day without an avalanche problem. Avalanches are unlikely. Instabilities within the snowpack are insignificant. 
  • Around 0.5 inches of QPF is forecast during daylight hours. Most of this will fall as rain below 4000 feet. 
  • Forecast snow totals range from just a trace to 6 inches, depending on temperatures and elevation. 
  • Any accumulating snow will be wet, and resistant to transport into the ravines during the day.
  • Colder temperatures this evening and increasing west wind are likely to create wind slabs on easterly aspects..if the upper end of forecasted snow is realized.  

The forecasting team this morning concluded that if today’s weather forecast holds true,  low snow totals will limit development of significant avalanche hazards during the day, other than wet sloppy surface snow. 

If temperatures swing cooler, several inches of accumulating snow at upper elevations will create conditions where small wind slabs could form on north and easterly aspects.  If we recieve the upper end of possible snow, wind slabs will be larger and may push the hazard rating towards MODERATE late in the day. 

Also keep in mind that melting has occurred over the last few days, bringing springtime objective hazards to the forefront. If you are in the mountains today be watching for:

Your avalanche, snowpack, or weather observations are extremely valuable to the forecasters at MWAC. Help create a more accurate avalanche forecast by submitting your observations.

  • The John Sherburne Ski Trail is closed at the third cut-over.  Please cross over to the Tuckerman Ravine trail at the yellow rope and walk down the hiking trail.
  • The Harvard Cabin is closed for the season.
  • The Lion Head Summer Trail remains closed for the season due to avalanche risk. The Lion Head Winter Route is open.

Regioni coperte