Avalanche forecast

Presidential Range

Mount Washington Avalanche Center
View on map

Avalanche danger

Sat
Alpine
2 · Moderate
Treeline
3 · Considerable
Below
1 · Low
Open full map
Out of date — this forecast expired 4 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Avalanches are likely on steep east-facing slopes (SE, E, NE) at middle elevations with wind drifted snow or stiff snow on the surface. Identify, carefully evaluate or avoid these freshly formed snow drifts before committing to traveling on or near them.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2.5

    25+ inches of new snow in the last 5 days (16 inches in the last 48 hours) combined with strong and shifting winds have created thick wind slabs on northeast, east and southeast aspects at middle and elevations. 

    Upper Elevations: It is likely these wind slabs are trending towards unreactive at upper elevations due to high wind speed. Start zones in gully tops may be wind scoured. 

    Middle Elevations: Unstable wind slabs of dry snow 1-2 feet thick existed in east facing ravines prior to Wednesday night’s storm. A recent storm snow total of 16 inches and strong west winds are the formula to create additional thick wind slabs on top of the existing slabs. Mixed precipitation and rain at this elevation during the morning yesterday created a melt-freeze crust capping dry snow, potentially with a little added dry snow on top. 

    Today’s considerable rating at this elevation reflects the likelihood of triggering a large avalanche if this surface refrozen is unable to bridge over any underlying instabilities. If the crust does have bridging properties, then triggering a large avalanche could be unlikely but would carry high consequences. 

    Keep a watchful eye on boot penetration and dig down looking for dry snow beneath that can fail and trigger a slide. Trusting supporting snow will be a judgment call based on what you find so gather as much information as possible before committing to a steep windloaded slope.  

    Poor visibility may make it difficult or impossible to assess slope conditions from a safe distance. To avoid triggering avalanches, you can steer around drifted pillows, stick to wind scoured terrain, or travel on slopes less than 30 degrees. 

    Low Elevations: Rain yesterday followed by cold overnight temperatures have reduced concerns for avalanches through wetting and refreezing. Watch for dry snow under thick pockets of new snow that may slide on very steep slopes.

Avalanche Discussion

25 inches of new snow fell in the last 5 days on strong shifting winds. Uncertainty of slab sensitivity at middle elevations due to rain in the morning yesterday keep the hazard rating at Considerable.

See MWAC Snowpack Tracker

9 inches of new snow on the 23rd was subject to strong northwest winds on the 24th creating sensitive wind slabs with a strong over weak structure resting on a melt-freeze crust.  

On top of this, over 15 inches of new snow (1.87 SWE) over the last 48 hours with strong southeast and west winds. Last night, strong northwest winds continued to transport snow at upper elevations. Typically strong continuous wind speeds work to scour the upper elevation, and decreases the sensitivity of remaining slabs at this elevation. Expect to find increasingly thicker and sensitive slabs at middle elevations in east facing ravines which are likely to be up to 3 feet thick.

Today is a good day for conservative decision making, and  consider avoiding avalanche terrain if you lack the visibility or skills to assess avalanche hazards above.

 

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.

Regions covered