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Presidential Range

Mount Washington Avalanche Center
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In sintesi

Small, human triggered wet snow avalanches will be possible as warm temperatures melt surface snow. Large avalanches are unlikely. Watch out for dangerous springtime mountain hazards which include falling ice, deep holes in the snowpack, undermined snow, and open water.

Problemi valanghivi

  • Loose Wet

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    Human-triggered wet loose avalanches are possible for the next few days as warm temperatures rapidly melt surface snow during the day and at night. Warming will create a surface layer of unstructured, wet loose snow which can move underfoot and possibly pull you from your feet in steep terrain. 

    The small wet loose sluffs should be easy to manage. The greater issue is a fall in steep terrain from tripping or getting pulled off your feet from the moving snow. You can manage this by moving to the side to let the loose snow pass. Be careful where falls have consequences.

Avalanche Discussion

Very warm temperatures today will increase the rate of melting snow, contributing to springtime hazards. 

The following spring hazards should be on your radar: 

  • Icefall and rockfall: Over the years many people have been severely injured or killed by falling ice in Tuckerman Ravine. The most hazardous locations are in the center and right side of the ravine, including Lunch Rocks, the Sluice, Lip, and Center Bowl. Warm weather and rain increase the potential for icefall to occur. Avoid spending time in high risk areas like Lunch Rocks or on the floor of the ravine in the fall line of ice in the headwall.
  • Glide cracks and waterfall holes: As the snowpack gradually gives way to gravity and creeps downhill, it pulls away from cliffs and leaves gaps. These gaps are the horizontal cracks that will soon appear in the steep terrain, most noticeably in the Lip and Sluice. These gaps can be deep enough to cause fatal injuries, especially around the main waterfall. 
  • Undermined snow: Meltwater flowing under the snowpack melts away the snow above, creating thin bridges of snow that can collapse. These will emerge at the tops of gullies (particularly on south-facing slopes) and in areas that have streams running, like the brook feeding the Little Headwall. The sound of running water can sometimes be heard under the snow and is a good indicator of this hazard.

Read more on Spring Mountain Hazards 

Spring Snowpack:

4/10 Oaks Gulf Observation, 4/11 Huntington Ravine Observation 4/12 GOS Observation

A uniform temperature gradient (isothermal snowpack) is now likely at all middle (ravine) elevations, effectively preventing the development of weak-snow layers and reducing concerns for instabilities within the snowpack. Moving forward, avalanche concerns are now limited to wet avalanches due to loss of strength from melting or new surface snow from spring storms.

 

Due to lack of snow and significant melting in the forecast, we have stopped forecasting for the low elevation band (below 3000 feet in elevation). Continue to use general caution in these areas and make slope-specific assessments of mountain hazards. 

The Lion Head Summer Trail is CLOSED due to increased avalanche hazard. The Lion Head Winter Route is OPEN and the most direct route to the Mount Washington Summit from Pinkham Notch. 

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. 

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