Latest avalanche advisory for Mount Washington’s Cutler River Drainage – Tuckerman and Huntington Ravines

Avalanche Advisory for Saturday, January 20, 2018

Huntington and Tuckerman Ravines have LOW avalanche danger. Natural and human-triggered avalanches are unlikely in all forecast areas.  Watch for unstable snow on isolated terrain features.  The Little Headwall is mostly open water or frozen waterfall ice.

Due to the open waterfall hole and 20’ crown line, the Tuckerman Ravine Trail is closed in the Ravine between Lunch Rocks and the Alpine Garden Trail. Please use the Winter Lion Head Route if going to the summit from Pinkham. Other routes to the summit from the east side are significant mountaineering routes.

 AVALANCHE PROBLEM: Very widely scattered areas of wind slab may be found in avalanche terrain today though the majority of our forecast area is scoured down to a hard icy crust. This icy surface, combined with strong winds, will present significant travel challenges today. This surface creates the opportunity for long, sliding falls which can end in a pile of rocks, melted holes in stream beds or trees if not arrested immediately. Our snowpack took a beating in last week’s rain storm and what’s left in its wake requires crampons and careful footing in steep terrain. Some snow showers this afternoon will not likely create significant avalanche problems though may challenge visibility a bit and further obscure refrozen footprints and other trip hazards.

 WEATHER: The current temperature on the summit is 23F with a west wind blowing at 82 mph. It is just below freezing at the Hermit Lake with no new snow on the board.  Two tenths of an inch of snow fell on the summit during snow showers early yesterday but otherwise the dry spell and warmup continues this morning.  Early this afternoon, a cold front swings through and drops the mercury to the mid-teens. A bit of mixed precipitation associated with the frontal passage may occur this morning, though the strong winds will be the most notable weather factor today. Anticipate west winds around 80 mph to continue through the day with gusts over 100 mph. Snow showers seem likely this afternoon as a secondary cold front passes with up to an inch falling by dark. The wind will moderate overnight with temperatures in the mid-teens and a decreasing west wind in the 50 mph range tomorrow.

SNOWPACK: At the Hermit Lake snow plot, there is 86 cm of hard, refrozen snow at the stake. A prolonged warming spell with rain late last week turned the upper portion of the snowpack into a knife hardness crust. That warmup ended with a period of freezing rain that glazed trees and snow surfaces at our elevation with ice which created little bonding opportunities for the several inches of snow which has fallen since. Most of that snow has been scoured out of our avalanche terrain and redeposited at lower elevations or in a few scattered and sheltered pockets. What didn’t blow out of the terrain already will be scoured out today as winds reach 100 mph. The blown out portion of the Lip below the Tuckerman Ravine Trail and the hard, refrozen debris pile remain visible in Tucks. Overall, surface conditions are hard and icy, making crampons, an ice axe and careful movement in steep terrain necessary.

Please Remember:
• Safe travel in avalanche terrain requires training and experience. This bulletin 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.
• Anticipate a changing avalanche danger when actual weather differs from the higher summits forecast. For more information contact the Forest Service Snow Rangers, the AMC at the Pinkham Notch Visitor Center, or the caretakers at Hermit Lake Shelters or Harvard Cabin.
• Posted 8:15 a.m., Saturday, January 20, 2018. A new advisory will be issued tomorrow.

Frank Carus, Lead Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2856

2018-1-20

Avalanche Advisory for Friday, January 19, 2018

Huntington and Tuckerman Ravines have LOW avalanche danger. Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features. The Little Headwall is an open stream and is not rated.

 AVALANCHE PROBLEM: New snow in the last 48 hours has been pushed around by wind, leaving isolated pockets of wind slab where scouring to the old refrozen surface did not occur. Small avalanches in isolated areas might not have the potential to bury a person in the absence of a terrain trap, but such an avalanche could easily cause a long sliding fall. The hard surface that is still prevalent in our terrain would be difficult for even the most skilled to arrest a fall.

Potential for and consequences of a long sliding fall may be a greater concern as you travel in our terrain today. Microspikes are no substitute for crampons and ice axe. Your ability to travel in a controlled manner on steep snow using crampons and ice axe is a necessity in current conditions. A high speed slide towards rocks, cliffs, or other exposed hazards can easily have dire consequences.

 WEATHER: Temperatures pushed into the 20’s F on the summit yesterday under partial clouds and wind in the 20-40 mph range. Today looks largely the same regarding temperature and cloud cover, with wind that will increase to around 40 mph late today. We might see a trace of new snow. Wind will increase tonight and tomorrow, ultimately approaching 100 mph. Air temperature should approach 30F on the summit tomorrow, though the extreme wind will make it feel much colder.

SNOWPACK: New snow earlier this week struggled to stick to the hard refrozen surface as it was transported by wind. Pockets of new wind slab do exist but are largely small and avoidable. If you’ve tried to dig in our snow lately, you’ve noticed that the hard surface snow is tough to penetrate with any tool. Instability will be limited to snow above this refrozen layer for the foreseeable future. We’ve said it already today and have all week, but we continue to stress the hardness of the refrozen snow surface. It provides good purchase for crampons but is smooth enough to easily accelerate a small fall to a slide for life in steep terrain. You would be hard pressed to arrest such a fall.

The John Sherburne Ski Trail holds similarly hard conditions under a thin veil of newer snow and will only provide an enjoyable ski option for the most desperate skiers and riders.

Please Remember:
• Safe travel in avalanche terrain requires training and experience. This bulletin 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.
• Anticipate a changing avalanche danger when actual weather differs from the higher summits forecast. For more information contact the Forest Service Snow Rangers, the AMC at the Pinkham Notch Visitor Center, or the caretakers at Hermit Lake Shelters or Harvard Cabin.
• Posted 7:45 a.m., Friday, January 19, 2018. A new advisory will be issued tomorrow.

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

2018-1-19