Lawinenlagebericht

Presidential Range

Mount Washington Avalanche Center
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Kernpunkte

Small, human triggered loose wet avalanches could occur on steep slopes at middle elevations from surface snow melted by warm temperatures and rain. Be mindful of dangerous springtime mountain hazards that include deep holes, falling ice, undermined snow, and open water.

Lawinenprobleme

  • Loose Wet

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    • Waldgrenze
    • Unterhalb der Waldgrenze
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    Possible
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    1

    Human-triggered wet loose avalanches are possible at middle elevations as warm temperatures continue to melt surface snow. Middle elevations have remained well above freezing for several days, creating a surface layer of unstructured, wet loose snow. Yesterday’s rain will have added to the surface melting. Upper elevations are unlikely to see this problem with temperatures below freezing and overcast skies. 

    This wet loose snow can move underfoot and potentially pull you from your feet in steep terrain.The wet loose sluff should be easy to manage by moving to the side and letting the loose snow pass. The larger concern is that this causes a fall in steep terrain by getting pulled from your feet or tripping in the moving snow. Be careful where falls have consequences and use careful route planning to mitigate your exposure over hazards like open holes, rocks, and trees.

Avalanche Discussion

Spring storms are tricky to predict. Ravine temperatures will start the day above freezing so there is some uncertainty if this precipitation will fall as snow or rain. When this change does happen, at middle elevations snow will be falling on a warm and wet snow surface and is likely to bond or melt into the old snow. 

Westerly winds tend to develop wind slabs the quickest throughout the Presidentials, but with heavy, wet snow and wind speeds of 25-35 mph through the day, there may not be enough wind to productively move this snow. 

Forecasters discussed the potential for the development of wind slabs, but with warmer temperatures, limited heavy snow, and moderate winds felt that this is unlikely. If these thin wind slabs develop, they will be found on eastern aspects at upper and middle elevations, but these will be small and isolated. As winds continue to build throughout the evening this may be when the most productive loading occurs. Red flags to look out for will be blowing snow from ridgelines as this will indicate if snow is being transported. 

Yesterday the summit recorded 0.53 inches of rain, this rain did not add or create new instabilities within the current stable snowpack. Unfortunately, it is likely that this accelerated more rapid melting of the snowpack, increasing the danger of springtime hazards (see below). Hermit Lake reported 9 cm of melted snowpack in the last 24 hours and 44 cm in the last 7 days.

With rain and days of warm temperatures the Presidentals currently have a very saturated snowpack. Now that temperatures are dropping, this surface will become firm and icy, beginning with higher elevations today and as the freezing line drops will also affect middle elevations.

Little Headwall in Tuckerman Ravine: The Little Headwall is unpassible due to high water flow and little snow remaining. Hiking down the Tuckerman Ravine Trail from the bowl of Tuckerman Ravine to Hermit Lake is the safest, easiest option.

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 develop in steep terrain and are currently visible in the Lip and Sluice. At the moment by the Lip, multiple waterfall holes are visible and open. A fall into any of 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. 
  • Other people: Sunny, warm spring days draw crowds of skiers to Tuckerman Ravine. Remain mindful of where and what others are doing around you. 

Read more on Springtime Mountain Hazards 

The bottom of the Sherburne Ski Trail has melted out and is now CLOSED below the yellow rope. Please help preserve the ski trail by removing your skis and walking down the Tuckerman Ravine Trail trail at the rope.

The Lion Head Summer Trail is CLOSED. 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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