Presidential Range

You can trigger a loose wet avalanche today where snow is softened by continued warm temperatures. Watch for snow surfaces becoming wet as a sign that snow stability has decreased. Sliding falls on a steep frozen snow surface may continue to be a dangerous hazard requiring the use of crampons and an ice axe, especially later today when temperatures drop back below freezing  Avalanche danger is LOW.  

The Tuckerman Inferno Pentathlon returns on March 20th for it’s 20th anniversary. This key fundraiser for the avalanche center has been re-imagined and now includes fat-tire biking, nordic skiing and snowshoeing before the run to Tucks and ski down. Check it out here.

The Winter Lion Head Route is the most direct route to climb to the summit from Pinkham Notch. The Tuckerman Ravine trail through the Bowl, and the Lion Head Summer Trail are much more exposed and pass through avalanche terrain.

Yesterday, effects on the snowpack from warming were limited to just the top few centimeters and mostly on sunny aspects. The bright sun was wonderful but temperatures were slow to rise past the freezing mark on the summit, just barely reaching 32F by 11pm. For much of the day temperatures remained in the high 20s above treeline, and in the 30’s below treeline. Observations from Huntington Ravine indicate that hard snow in the shade did not soften at all, and sun exposed snow in the fan softened just enough for a bit of boot penetration. 

Today’s avalanche problem is driven by warming snow. Temperatures overnight were above freezing at middle and lower elevations and will increase through the day giving ice crusts and wind hardened surfaces time to melt and become soft. Strong west wind will play a role to limit the effects of the warm air softening the snow, but as any Mt. Washington spring skier knows, this can be hard to predict. Firm surfaces high in the gullies most exposed to the wind may soften only little, despite the warm air temperatures. 

Looking ahead to Friday and the weekend. Temperatures will drop tonight back to the lower 20’s and all softened, wetted snow will refreeze creating an icy melt freeze crust. We’ll be looking today to see how deep into the snowpack free water penetrates to try and estimate how thick the crust will be. 

Slab avalanches wet or dry in today’s forecast? The effect of warming on a previously unreactive hard slab, which is currently dominant in our upper snowpack, is difficult to forecast. We don’t expect avalanches from this layer, but it’s worth traveling as if one could occur. Travel one at a time, continuing to evaluate the consequences of an avalanche and factor that into your decision making.    

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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 here. 

Listen to the weekly MWAC Outreach Podcast provided by Ski The Whites. Discussions include snowpack information, weekend outlook, and general avalanche related info. 

Our next free online event is coming up Thursday, March 18 @ 7PM -Women’s Backcountry Talk- A Free Zoom Webinar. Signup is required. 

The Harvard Cabin is open for camping only with no entry allowed inside the cabin. There is no access to the breezeway at HoJos.

Please Remember:

• Safe travel in avalanche terrain requires training and experience. This forecast is just one tool to help you make your own decisions in avalanche terrain. You control your own risk by choosing where, when, and how you travel.
• Avalanche danger may change when actual weather differs from the higher summits forecast.

For more information contact the US Forest Service Snow Rangers, AMC visitor services staff at the Pinkham Notch Visitor Center, or the caretakers at Hermit Lake Shelters or seasonally at the Harvard Cabin (generally December 1 through March 31). The Mount Washington Ski Patrol is also available on spring weekends.