TUCKERMAN RAVINE HAS MODERATE AND LOW AVALANCHE DANGER. The Little Headwall, the Lower Snowfields, and Left Gully all have Low avalanche danger. Human triggered avalanches are unlikely except in isolated pockets on steep snow covered open slopes and gullies. Normal caution is advised. All other areas in Tuckerman have Moderate avalanche danger. This includes the Hillmans Highway, Bowl, Headwall, Lip, Sluice, and Right Gully. Natural avalanches are unlikely and human triggered avalanches are possible. Use caution in steeper terrain.

HUNTINGTON RAVINE HAS LOW AVALANCHE DANGER. Human triggered avalanches are unlikely except in isolated pockets on steep snow covered open slopes and gullies. Normal caution is advised.

It has warmed up a little bit over night into this morning to the current of 12 degree F. As discussed yesterday there is a strong temperature gradient in the upper 30-40 cm which will facilitate the movement of vaper in the snowpack. I found a gradient of up to 8 degrees C within 10 cm of snowpack this morning. This is a big temperature difference and has begun the faceting process. Small faceted crystals were seen in the .5mm to 1mm range. Over the next couple of days you should continue to see changing crystals in the upper foot of the snowpack. The loose snow beneath the ice layer is low in density with many air channels allowing easy movement of vaper. As a result, these facets may grow rapidly. As faceted crystals grow larger the bonds between them become weaker increasing instability in the snowpack. Whether it will make a big stability difference is yet to be determined, but I think it will be worth watching particularly at higher elevations where thin crusts are possible. New snow also came in with the front yesterday so some slabs are possible in lee areas which should not be bonded well with the ice crust.

Snow showers are forecasted for later today so watch for an increasing avalanche danger. With moderate West winds likely, new slabs may occur in both ravines. Loading would occur on the ice layer in most locations, so a weak bond at the interface is likely. The ice layer is textured which should help a bit with adhesion, but expect easy shears between the two layers.

THE LION'S HEAD WINTER ROUTE IS OPEN. Follow the orange Lion Head signs off of the Tuckerman Ravine trail about 1.75 miles up from Pinkham. This is a difficult steep route so crampons, ice axe, and mountaineering skills are essential.

Coverage on the John Sherburne ski trail is improving but the waterbars are still not quite filled in and you should expect rocks here in there just below the snow.

 
PLEASE REMEMBER:
 
• Any new precipitation may increase the avalanche danger, this includes wind transported snow.
 
• Obtain latest weather forecast before starting out.
 
• For more information, contact the U.S. Forest Service Snow Rangers: AMC at Pinkham Notch Visitor Center or Hermit Lake Shelters.
 
• This bulletin expires today at midnight and the next avalanche bulletin will be issued tomorrow.

 
Christopher Joosen, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2856

	TUCKERMAN RAVINE
	Hillman's Highway
	Lower Snowfields
	Little Headwall
	The Bowl
	Headwall
	The Lip
	Left Gully
	Right Gully

	HUNTINGTON RAVINE
	Escape Hatch
	South Gully
	Odell's Gully
	Pinnacle Gully
	Central Gully
	Yale Gully
	Damnation Gully
	North Gully

 
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