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Human-triggered avalanche in Left Gully

Events:

On January 22 at 3:20 pm, a skier was caught by an avalanche triggered by his party and carried from near the top of Left Gully almost to the floor of the ravine. A ~six inch slab of new and wind deposited snow released from the uppermost start zone from skier 2’s feet as skier 1 made their first turn. Skier 1 was quickly swept into and under the moving debris and lost their skis and poles. When the flow stopped, they found themselves buried face down, fortunately with their head very near the surface, but the rest of their body buried by two feet or more of debris. They were unable to move but could raise their head for a breath.

Skier 2 did not see their friend and skied away. Ultimately, they alerted others down by the Connection rescue cache. Bystanders closer to the scene began to dig out skier 1. Others arrived, including Hermit Lake and Harvard Cabin caretakers and later, snow rangers, to assist.

Analysis:

Just prior to the avalanche, a snow ranger suggested to the two skiers, who did not have beacons, shovels or probes, that they ski the lower angled slope between Right Gully and LC or the lower section of Left, if they skied anything at all. They later told snow rangers that the excitement of new snow drove them to the top and into the upper start zone where the incident then unfolded. These two were very helpful to the community by honestly sharing their story with snow rangers.

There were no natural avalanches reported that day which carried a Moderate danger rating, though the forecast included possible human triggering of D1-2 wind slabs. This pair was among many poorly equipped skiers or skiers traveling alone. Low visibility marked conditions for the day with periods of moderate snow squalls and minor wind loading at the tops of gullies.

Reading the forecast carefully, applying safe travel techniques, and carrying the proper equipment are fundamental to recreating in avalanche terrain. It is critical to acknowledge that the majority if avalanche incidents and fatalities occur in Moderate danger rating days where the avalanche hazard may include the potential for isolated, stubborn but large avalanches OR widespread, smaller avalanches, such as this day. Both can carry real consequences.

Left Gully, Tuckerman Ravine.  Photo taken three days after the event: 1/25/2021

Long Sliding Fall – Tuckerman Ravine Trail

Events:

On the morning of Saturday, January 9, 2021, two 20 year old males were ascending the Tuckerman Ravine Trail. Around 11 am, witnesses noted these two individuals on foot, falling near the rollover at the top of the ravine. Both individuals fell around 500 vertical feet, impacting exposed boulders and ice along the way. One came to a stop on a ledge above the final ice cliff while the other fell past this point and was described as being airborne until he landed on his upper back in the snow below the ice cliff.

The incident was reported to snow rangers shortly after noon. Both patients were reportedly conscious, though one potentially had an altered level of consciousness. A hasty team departed Hermit Lake with an EMT medical pack and AED. Additional personnel followed close behind with technical rescue gear.

At 12:30 pm, en route to the ravine, the hasty team encountered one patient walking downhill with a bystander. This was the individual who had landed at the base of the ice cliff. His clothing was wet, so he had been stripped of the wet clothing and given a dry jacket, helmet, and trekking poles. After a patient assessment, it was determined that he should continue on foot, assisted, to the USFS cabin at Hermit Lake for further assessment and rewarming.

Upon arrival at Lunch Rocks, snow rangers determined that the safest and most expedient access to the 2nd patient was to ascend steep snow to the right of the patient, rather than directly up the ice cliff. Snow rangers reached this patient shortly after 1 pm. He was chilled, as he had been sitting on the snow for about 2 hours, so he was given an extra jacket and gloves. The patient was provided a harness and rope belay, and guided down steep snow to the ravine floor. A technical litter and anchor had been prepared, but was deemed unnecessary as his injuries were limited. He was also comfortable walking to the cabin for further assessment.

Rescuer and patient looking across the ravine at exposed hazards lower in the runouts of Chute and Center Headwall, which are not yet full-length ski runs.

Analysis:

Both individuals were equipped with leather hiking boots and microspikes. The pair had trekking poles in the mix, but no ice axes. They were navigating using the GPS in their phones. One individual had been on the same route 4-5 times before, while the other was there for the first time. Their objective was to ascend the Tuckerman Ravine Trail, and presumably continue to the summit.

One patient reported reaching a point where his microspikes provided insufficient traction. He said he fell forward like a starfish, slid over an ice bulge, and continued falling. His partner saw this happen, lost his footing, and subsequently fell as well. Both individuals impacted multiple exposed boulders and ice bulges during their descent.

This season has seen slower snowpack development than recent years. December accumulation took a big hit from the Christmas rain event, and January has provided less than 6” of new snow so far. As such, exposed hazards abound and present a minefield of challenges and consequences.

Looking upslope from where patient #2 landed at the top of the ice cliff.

At the time, the aspect they were in was intermittently exposed to solar radiation through fog and scattered clouds. Perhaps more importantly, temperatures were relatively warm (25F at the summit), so the snow may have been more forgiving to soft boots than otherwise would have been the case. However, this very well could have provided a false sense of confidence that evaporated once they had to navigate bare ice with inadequate traction. The two hikers encountered difficulties near the top of the ravine, where wind often scours the soft snow and leaves a hard, icy surface.

In the winter, the Tuckerman Ravine Trail through the headwall becomes a true mountaineering objective, complete with steep sections of hard frozen snow, cliffs of ice, and snow slopes capable of producing an avalanche. Individuals choosing to climb this route should be prepared with proper mountaineering equipment and the skills to use them. Rigid boots, crampons, two ice axes, avalanche rescue gear (beacon, probe, and shovel), and a roped system to protect against a long dangerous fall are often required to climb through this steep section safely.

Ultimately, these individuals were incredibly lucky. Despite numerous bumps and bruises, neither experienced significant trauma. Despite inadequate gear for conditions in the ravine, multiple bystanders were willing to provide equipment, support, and reassurance, and to seek qualified help to extricate patients from steep terrain.

Mount Washington is relatively accessible, and oftentimes people manage to get away with an objective despite a lack of preparation and appropriate equipment. However, this accessibility means there are also plentiful resources available. Trip planning must consider weather and avalanche conditions, which are provided locally by the Mount Washington Observatory and Mount Washington Avalanche Center. Trip planning must consider trail conditions and suggested routes. Caretakers provide this readily at Hermit Lake and Harvard Cabin, as well as AMC staff at Pinkham Notch. Maps and appropriate equipment can be acquired from numerous retail locations and guide services in the area. Local guide services are also a great way to learn to use said equipment, and learn best practices for movement and decision making in the mountains.

While we all learn from mistakes, we can stack the cards in our favor to avoid mistakes such as these. Seek relevant information, don’t skimp on safety gear, and embrace continuous education in mountain sense.

Long Sliding Fall – Chute

March 9, 2020. AMC Hermit Lake Caretaker reported seeing a person falling end-over-end “tomahawking” the length of Chute in Tuckerman Ravine around noon. The Caretaker and Snow Ranger responding were pleased to find that the patient had no apparent injuries. The skier walked downhill to Hermit Lake and was assisted to the road by snow machine.

It was reported at the time of the fall, the skier was still climbing up somewhere near the top of Chute, wearing leather boots with micro-spikes and no ice tool. He had ski boots and skis on a back pack. The snow was still firm, barely softened by the sun.

Safe climbing of steep snow, especially hard snow requires the skilled use of stiff boots, crampons and an ice axe or two to prevent a fall from occurring. When climbing without the protection of a rope belay, preventing a fall from happening is a climber’s/skier’s primary means of safety since arresting a fall with an ice axe is difficult with, and impossible without.

Video here: https://www.instagram.com/p/B9j0hA-HtDA/?igshid=15m8w2rcfwucf

 

 

 

Sliding fall, Chute, 2019-5-12

Sliding fall, exit of Right Gully

Close call: Fall into deep waterfall hole

As winter turns rapidly to spring, a number of hazards become prevalent in the steep terrain of the Presidential Range and particularly the Headwall of Tuckerman Ravine. Waterfall holes, glide cracks or crevasses, moats around cliffs and rocks, and other deep holes open as the thick snowpack melts. A fall into these holes, which often also have significant amounts of cold flowing water which can quickly cause hypothermia, can be very difficult to escape or be rescued from. Such accidents have resulted in several fatalities in Tuckerman Ravine. A lucky skier had a very close call in this type of accident yesterday.

At 1:58 PM on Monday, April 22, a skier fell over the Tuckerman Ravine headwall and into one of several waterfall holes. Partners and bystanders quickly initiated rescue efforts and also called 911 for emergency response. Unsure of where under the snow the fallen skier was, a beacon search was initiated and could have been helpful, though this was a non-avalanche accident. At 2:18 pm, after 20 minutes out of view to the rescuers, the subject climbed out of a different hole in the snow and slid down to the rescue party below him in the slope. He had lost his skis, poles, and pack.

The subject was alert, oriented, and able to walk but in pain from several impacts during the fall. He was also cold and wet from spending most of the 20 minutes in very cold flowing water, though not submerged. The rescue party quickly changed his clothes to drier ones. They wrapped him in a sleeping bag and briefly transported him in a rescue litter obtained from the nearby Connection Cache of emergency supplies. In effort to warm the subject, the rescue party then helped the subject begin walking down the Tuckerman Ravine Trail towards Hermit Lake.

The fall line glissade track just right of center leads up to waterfall hole and accident site, with partners of the subject shown helping him walk downhill.

Meanwhile, U.S. Forest Service Snow Rangers were notified of the incident by emergency dispatchers. They travelled to Hermit Lake with urgency, aware than similar accidents have historically been fatal. Upon arriving at Hermit Lake, Snow Rangers were told by the AMC caretaker that the subject had extracted himself from the waterfall hole and was walking, with aid, down to Hermit Lake. They proceeded up the trail, meeting the rescue party at 3:20 PM. The subject, still alert and oriented but now warmer, was transported to Pinkham Notch via snowcat and released to the care of friends.

This positive outcome should be regarded as quite lucky and be taken as a warning for all who travel on steep snow slopes in spring conditions in our mountains. Had the subject, who was a strong athlete and also a climber, been unable to self-extricate himself from the waterfall hole the outcome could have been far worse. Many of these deep holes in the snow are impossible for even the strongest individual to climb out of. Extricating a person from these holes can be very dangerous for rescuers and is difficult to accomplish in a sufficiently timely manner to save a life. We know the subject would urge you to learn from this accident, giving potentially deep holes and glide cracks in the snow a wide berth and taking care to not fall above one.

The rescue initiated by partners and bystanders of the subject was a positive example we would also like you to learn from. Partners were paying attention to each other and able to quickly initiate a rescue. They had sufficient dry clothing and emergency supplies to provide proper care for the subject. Several emergency medical professionals observed the accident and immediately helped rescue efforts. Rescuers had knowledge that a litter and hypothermia wrap materials were available in nearby Connection Cache and used them. All individuals on the scene had avalanche rescue gear, as large wet slab avalanches were forecast as unlikely but not impossible that day. While a call was made for professional rescue, this group realized that they could provide timely aid to the subject and took appropriate action that could have resulted in an effective evacuation had professional rescue been delayed or unavailable. This self-reliant level of accident response is commendable. It is also the level of response that everyone travelling in the backcountry should be prepared for, every time you’re out.

Please learn from this accident to have a safer spring ski season, and see you on the hill!

Human Triggered Avalanches

On April 7, 2018, seven avalanches occured in Tuckerman Ravine. All were human triggered. This write-up discusses the weather and snowpack that lead up to these events, an objective summary of the events, and an analysis of factors that lead to at least five people being caught in one of the avalanches.

Weather

In the week leading up to April 7, 2018, our snowpack saw two rain events. The first was March 29 and 30 which delivered 0.75” of rain followed by 0.32” of rain on April 4. Both of these rain events were followed by hard freezes. On Friday, April 6, light snow showers began just after noon and continued through sunrise the following day. By the time snowfall stopped, the snowplot at Hermit Lake recorded 16cm (6.3”) of 9% snow while the summit recorded between 7 and 8” (this is an estimate based on hourly observations as the total snowfall was recorded as less due to excessive blowing snow) of snow. When snowfall began on Friday, wind at the summit was around 30mph from the south. Overnight, wind direction shifted to the west and speeds increased to 60-70mph. Weather on Saturday April 7 was clearing skies, winds diminishing to around 40mph from the west, and temperatures in the single digits on the summit and reaching into the 20sF at Hermit Lake. This weather pattern built a robust melt-freeze crust over which wind slab was built from new snow and wind April 6-7. This touchy wind slab was the avalanche problem involved in all known avalanches on April 7.

Summary of Events

During the morning of April 7, three avalanches were intentionally triggered by skiers. All three were ski cuts, two occurring in Lobster Claw (both SS-ASc-R1-D1.5-I) and one occurring on the rollover of the Little Headwall (SS-ASc-R1-D1-I). Slab depths were up to 14” and all occured on a layer of softer snow immediately above the melt-freeze crust. Of note in the Little Headwall was that the second skier through was able to trigger the “hangfire”, or slab remaining above the crown of the initial avalanche.

Examining the crown in Little Headwall. MWAC photo.

We have less definitive information on the Left Gully and Chute avalanches, which occurred shortly before and after the Hillman’s Highway avalanches, respectively. We believe that no one was caught or carried by either avalanche, both of which were triggered unintentionally. Left Gully, which was rated Moderate, produced an avalanche from a relatively thick though isolated pocket, while Chute, which was rated Considerable, produced a larger in area avalanche from a thinner slab. Both are estimated SS-ASu-R2-D1.

Unlike the other avalanches this day, the avalanches in Hillman’s Highway did involve a number of people being caught and carried. At approximately 2:00 pm, at least 40 people were climbing and skiing in Hillman’s. An individual climbing uphill from the looker’s right fork to the looker’s left fork triggered the initial avalanche as they entered the looker’s left fork. This person was not carried in the slide. The crown of this avalanche was approximately 300’ below the top of Hillman’s and ran ⅔ of the way down (SS-AFu-R2-D2-I). Of the many people in the avalanche path, at least 5 were caught and carried. USFS Snow Rangers responded to the incident and identified one injured skier who was ultimately transported to Pinkham Notch with a back injury that was not life threatening. Another individual who was also caught and carried sustained a minor injury to their hand.

Looking at the crown of the first avalanche in Hillman’s Highway. Photo by Kurt Schleicher.

The second avalanche was triggered around 2:30pm, within minutes of the initial Snow Ranger team arriving on scene. The trigger was unknown at the time, but consensus of bystanders is that this second avalanche was triggered by the same individual who triggered the first, having topped out on the ridge and beginning to ski the hang fire slab above the initial crown. This second avalanche was smaller (SS-ASu-R2-D1-I) and luckily did not capture any people or result in injuries.

Analysis

Many opportunities for learning are presented by this day which which fortunately did not involve more serious injuries. First, it’s an excellent reminder that avalanche conditions can develop during the spring months which bring crowds of backcountry skiers to Tuckerman Ravine. As with any time of year, these avalanches can widely vary in size and character. Avalanches can be of minimal concern on certain spring days, but April 7 was a day with avalanches as the primary concern for alpine travelers. On any such day, anyone venturing into avalanche terrain should bring a beacon, shovel, probe, and knowledge to use them effectively.

Carrying avalanche rescue gear is a cardinal rule for travelling in avalanche terrain. Another is travelling one at a time through areas exposed to avalanche danger. This requires recognizing avalanche terrain, which includes both terrain capable of producing an avalanche and terrain threatened by avalanches. A phrase often heard in the courtyard is, “It’s just Hillman’s”. All of Hillman’s Highway is avalanche terrain. On top of that, it’s easily the biggest gully in Tuckerman Ravine and is particularly confined. Exposing one person at a time to avalanche danger is crucial, particularly on a day like April 7. It’s likely that nobody would have been injured had this been the case.

Avalanche danger was Moderate in Hillman’s Highway on this day, which forecasts natural avalanches as unlikely and human triggered avalanches as possible. These possible human triggered avalanches can be either small and in many areas or large and in specific areas. With a number of similar avalanches in other Moderate rated areas, we consider April 7 as a small avalanches in many areas kind of day. It’s worth noting that a Moderate rated day for large avalanches in specific areas is sometimes referred to as “scary moderate”, in which you’re less likely to find signs of instability but potentially able to trigger a large avalanche. Further, remember that even small avalanches can ultimately be fatal.

The Chute was rated Considerable and produced a slightly larger in area avalanche from a thinner slab. The primary distinction between Moderate and Considerable is increased likelihood of both natural and human triggered avalanches with greater chance for larger avalanches. Other Considerable areas received little if any traffic, which we suspect is a reason that more did not produce avalanches.

All avalanche problems exhibit some degree of spatial variability. This means that the snowpack is not uniform across the terrain and avalanches can often only be triggered from specific locations. A number of people can travel on a slope, particularly one as large as Hillman’s, before someone finds this specific location and triggers an avalanche. Tracks on a slope do not mean it’s safe to ski or climb.

The Little Headwall was not rated on April 7 for lack of snow, but did have enough snow in one isolated pocket to produce an avalanche. Unrated terrain, which encompasses all of our terrain early and late in the season, can produce avalanches. The human triggered avalanche in Central Gully on Dec 1 of this season is another example. We do issue danger ratings for areas of most concern during the bulk of the season in Tuckerman and Huntington Ravines, but avalanche activity is not confined to areas forecast on a particular day.

Finally, we should touch on ski cutting. The avalanches in the Little Headwall and Lobster Claw were intentionally triggered in a controlled manner through ski cutting. This process of intentionally skiing a specific part of a slope likely to trigger an avalanche, with speed and from one safe zone to another, is an advanced practice and is only appropriate under certain conditions. A book could easily be written about the practice of ski cutting, but a simple explanation is that it is only wise when you possess a high degree of certainty about what the the ski cut will produce AND the consequences if you’re wrong. In particular, ski cutting is inappropriate when an avalanche may initiate above you. On April 7, we had the rare conditions for our terrain in which instability was limited to surface slabs and individuals were able to ski potential start zones for isolated and small pockets of wind slab. Certainty was high both in terms of anticipated result and consequences for being wrong, and avalanches above the individuals ski cutting were nearly impossible. Further, other people were not in the potential avalanche runout zones.

Brody Leven ski cutting in Lobster Claw. Photo by Lincoln Benedict.

The human-triggered avalanches on April 7 did result in injury, but everyone on the mountain lived to ski and climb another day. Luck certainly contributed to this relatively positive outcome, as did the relatively small but widespread type of Considerable and Moderate avalanche danger that day. We who like to travel in avalanche terrain rarely get such valuable lessons without more serious outcomes. Great turns can be had with minimal risk on such days, but only by choosing terrain that matches your preparedness, knowledge, certainty, and skill level.