Avalanche Advisory for Friday, January 22, 2016

All forecast areas of Tuckerman Ravine have MODERATE avalanche danger.  Natural avalanches are unlikely and human-triggered avalanches are possible. Evaluate snow and terrain carefully. Lobster Claw, Lower Snowfields, and the Little Headwall are not posted due to lack of snow cover. Exercise caution in these areas.

Huntington Ravine is under a General Avalanche Bulletin. General Bulletins are issued when instabilities are isolated within forecast areas and are issued every three days or earlier if conditions warrant. Forecast areas in Huntington have less well-developed snowfields to produce avalanches, but understand instabilities in these smaller locations may exist.  It is critical that you assess snow and avalanche conditions if venturing into Huntington.

AVALANCHE PROBLEM: Wind slabs remain the primary avalanche problem. High winds over the past several days have forged hard slabs in most of our forecast areas. These slabs are strong and mostly resistant to human triggering but it may be possible to find the thin spot which could propagate a crack.  Where these slabs exist, especially in steeper terrain you could find a thin spot and perforate this slab, causing a section to fail. The possibility of triggering something is on the lower end of the rating but the consequences of triggering one of these thick and dense slabs is severe. Be on the lookout for hollow sounding areas in well sheltered locations.

WEATHER: Though winds will abate through the day, lingering moisture to the west will flow up and over the mountain creating fog at ground level during the morning hours. This fog will diminish as downsloping wind dries out. Temperatures are starting out in the -10F (-23C) range but will rise into the single digits above zero later on. Winds from the NW at 50-70mph (80-112kph) will diminish to the 35-50mph (55-80 kph) range. All in all a remarkably average January winter day is on tap.

SNOWPACK: Since our prolonged period of high winds began on Tuesday, we have received no significant snowfall. During this period, the summit recorded peak gusts of 127mph on Tuesday, 97mph on Wednesday, 112mph yesterday. In short, our snow pack in the Ravines, as well as the Sherburne Ski Trail, is wind hammered. The rain crust and water saturated refrozen snow and ice from a couple of weeks ago is showing in many places on the Sherburne. We’ll continue to look for this layer which may exist at some depth in certain areas of Tuckerman. In sheltered areas the crust is likely deep below a travelers stress bulb. In shallower areas, it may serve as a weak layer, but this remains a hypothetical. Other weak layers, in the form of varying slab densities, from mid-storm wind velocity changes would also be worth looking out for. Huntington Ravine may harbor some wind slabs at the base of Central, Pinnacle and scattered through Odell and South gullies but good visuals this morning show that the northern gullies have limited snow coverage so expect to find long stretches of low angle ice.

Barring some unforeseen circumstances, we will change over use from the Lion Head summer trail to the winter route starting tomorrow morning due to the growing bed surface for avalanches on the summer trail.

Please Remember:

  • Safe travel in avalanche terrain requires training and experience. This advisory 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 the Harvard Cabin.
  • Posted 8:30 a.m. January 22, 2016. A new advisory will be issued tomorrow.

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

2016-01-22

Avalanche Advisory for Thursday, January 21, 2016

All forecast areas of Tuckerman Ravine have MODERATE avalanche danger. Heightened avalanche conditions exist on specific terrain features.  Natural avalanches are unlikely and human-triggered avalanches are possible. Lobster Claw, Lower Snowfields, and the Little Headwall are not posted due to lack of snow cover. Exercise caution in these areas.

Huntington Ravine is under a General Avalanche Bulletin. General Bulletins are issued when instabilities are isolated within forecast areas and are issued every three days or earlier if conditions warrant. Forecast areas in Huntington have less well-developed snowfields to produce avalanches, but understand instabilities in these smaller locations may exist.  It is critical that you assess snow and avalanche conditions if venturing into Huntington.

AVALANCHE PROBLEM: Wind slabs continue to be the primary avalanche problem.  Clouds and blowing snow continue to veil the Ravine which will limit the ability for an overall quality assessment.  Existing slabs will likely be strong and stubborn to human impacts bridging over weak layers due to very high winds in the past 72 hours.  However, expect the outer extent of some of these slabs to be thin and more prone to fracture and failure, initiating into the thicker hard slabs nearby. If this occurs expect the potential fracture to travel greater distances than in softer slabs.  Anticipate the possibility for an avalanche that could encompass the entire snowfield, only limited by terrain features such as cliff bands and ice features.  In very sheltered lee areas of W to NW winds you may find isolated softer slabs that could be easier to trigger.  These softer snowfields are only a small percentage of the overall snowpack and less of a concern than the higher consequence hard slab avalanche.

WEATHER: Full winter ice cream headache conditions continue today due to below zero F temperatures and very high winds.  Visibility is expected to increase later today and then even more tomorrow as a high pressure slides in.  Unfortunately, the storm that will slap areas south of us with multiple feet of snow shouldn’t do much for our mountains, but more on that tomorrow.  Skiing may actually be pretty good if you head into southern New England this weekend. Slight warming, as well as a significant wind drop, will occur over the next 36 hours making the mountains more user friendly as we move into Saturday and Sunday.  Expect winds to slowly taper to as low as 15mph by Friday night.

SNOWPACK: As discussed yesterday we have limited snowpack information and are basing ratings on the past several days of weather and historically like events.  Winds will stay high today, gusting into the 90’s mph (150’s kph), eventually backing off during the overnight.  However, even with the tremendous transport power of these winds there is limited snow available in the alpine zones, so generally we are on a trend of increasing stability.  Following high wind events on Mount Washington, where winds are sustained for long periods over 100mph (160 kph), the mountain is left with what we dub “Steel Slab”.  This very hard and strong slab has enormous bridging capability as well as tensile strength.  The outer edges, or occasionally mid-snowfield, are thinner and less tolerant of your weight and impact bulb.  These locations are typically the trigger locales for the adjacent stronger thick hard slabs. The spatial variability and the ability to navigate the proverbial minefield of differing slab thickness is difficult.

Please Remember:

  • Safe travel in avalanche terrain requires training and experience. This advisory 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 the Harvard Cabin.
  • Posted 8:30 a.m. January 21, 2016. A new advisory will be issued tomorrow.

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

2016-01-21

Huntington Photos – January 20, 2016

The clouds cleared today from Huntington while Tucks was still socked in. Good visibility confirmed our suspicion that the terrain would have been scoured hard by strong winds.

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Avalanche Advisory for Wednesday, January 20, 2016

All forecast areas of Tuckerman Ravine have MODERATE avalanche danger. Heightened avalanche conditions exist on specific terrain features.  Natural avalanches are unlikely and human-triggered avalanches are possible. Lobster Claw, Lower Snowfields, and the Little Headwall are not posted due to lack of snow cover. Exercise caution in these areas.

Huntington Ravine is under a General Avalanche Bulletin. General Bulletins are issued when instabilities are isolated within forecast areas and are issued every three days or earlier if conditions warrant. Forecast areas in Huntington have less well-developed snowfields to produce avalanches. How the recent strong winds have affected snow coverage in Huntington remains to be seen. It is critical that you assess snow and avalanche conditions if venturing into Huntington.

AVALANCHE PROBLEM: If we could see into the ravines this morning, what we expect we’d see is a lot of hard wind slabs left over from the wind loading that has been taking place over the last couple days. Wind slabs are your primary avalanche problem. The size and extent of the problem will depend largely on what slopes have avalanched recently and when, which we are unable to determine as of yet due to the thick fog. The existing slabs will likely be strong and stubborn to human impacts, but if you should find the sweet spot and trigger an avalanche today, it will be in an unforgiving layer of dense hard slab. As long as winds are able to find snow to transport into the ravine, we cannot rule out the potential for a naturally triggered avalanche today. Areas such as the Lip, Center Bowl, and Chute are at the upper end of the Moderate rating.

WEATHER: It’s been a wild couple days up here weather-wise. Yesterday’s peak gust didn’t get as strong as forecast, but 117mph (190kph) isn’t bad. Persistent snowfall on Monday brought roughly 5” (7.5cm) of new snow to the summit, which has been followed by the fog and very strong westerly winds. These winds have kept blowing snow in the hourly observations at the summit for more than 48 hours straight. Today you’ll face persistent strong winds, cold temperatures, and some additional blowing snow. These are certainly are “full winter conditions.” Thankfully, we are trending toward clearing conditions which will hopefully provide some visibility this afternoon.

SNOWPACK: As mentioned, we have been unable to get even visual observations of what’s happened in the last couple days here, so we don’t have first-hand data regarding the snowpack. Looking at the weather for the last few days and the forecast, we believe we may still have wind loading taking place today as a slow shift in wind direction from the W to the NW may access snow that had settled into small lee features in the alpine zone. Surface slabs are often quite strong after this type of event, especially in areas where it is thickest. However, due to the lean coverage this year we have a lot of places where the slab may be thin enough for you to impact a weak layer, such as edges (where slabs tend to naturally become thinner) and near buried rocks or trees. Your ability to navigate the proverbial minefield will be an important factor in keeping safe. Additionally, the currently disjointed nature of our terrain can allow for some very sheltered location to harbor some softer slabs.

Please Remember:

  • Safe travel in avalanche terrain requires training and experience. This advisory 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 the Harvard Cabin.
  • Posted 8:30 a.m., Wednesday, January 20, 2016. A new advisory will be issued tomorrow

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

2016-01-20

Avalanche Advisory for Tuesday, January 19, 2016

This advisory expires tonight at 12:00 midnight.

All forecasted areas of Tuckerman Ravine have Considerable avalanche danger. Dangerous avalanche conditions exist. Natural avalanches are possible and human triggered avalanches are likely. The only exceptions to this are the Lobster Claw, Lower Snowfields, and Little Headwall which remain not posted due to an overall lack of snow in these areas.

Huntington Ravine is under a General Avalanche Bulletin. General Bulletins are issued when instabilities are isolated within forecast areas and are issued every three days or earlier if conditions warrant. Forecast areas in Huntington have less well developed snowfields to produce avalanches. However, bed surfaces do exist, particularly in Central, Pinnacle, Odell, and South gullies. Climbing today in Huntington will be very challenging due to weather and very poor visibility. You will not be able to visually assess the routes for avalanche potential before you have already exposed yourself.

AVALANCHE PROBLEM: Wind slabs are the primary threat again today. Although snow stopped falling throughout much of the region a while ago, on Mt. Washington, wind transport of recently fallen snow is causing elevated avalanche hazard. Additional upslope snow is expected today which will mix with the blowing snow as winds remain remarkably strong. These factors lead us to believe there will be numerous avalanches in Tuckerman, with some paths possibly running multiple times. Poor visibility will limit your ability to assess your location in relation to the avalanche runout paths. Expect runouts to be farther than they have been yet this season.

WEATHER: Strong winds in excess of 100mph (161kph) will be buffeting the mountain throughout the day while temperatures stay brutally cold. Be cautious if traveling in the mountains, even below treeline. Upslope snow showers will take place today, hopefully giving us a few more inches of snow. The Obs is calling for 1-3″, but the NWS has made mention of 4-6″ possible in the notches and northern Coos county. I won’t hang my hat on the potential for 6″, but be aware that it will be snowing. The sunshine you’ll see in the valleys most likely won’t be found on Mt. Washington today.

Yesterday snow fell lightly though the day on W winds with increasing speeds. The Obs reports 5.5″, but they had blowing snow filling their can deeper than that, so exact numbers are uncertain. The same goes for our snowplot at Hermit Lake; drifting was widespread on our collection boards.

SNOWPACK: Due to persistent snow yesterday and the blowing snow today, we have not seen the mountain since Sunday afternoon. I expect we began an avalanche cycle yesterday which will continue today. Snow began on light winds in the teens (mph), leaving a weak layer which would have been loaded on top of by slab formed during the strong winds later in the day. This trend continues as of this morning. While we can’t say which areas may have already avalanched, I do believe today’s conditions are conducive to multiple avalanches in the same path. Hard slabs will be forming and building. When these release, their impressive density can send them farther down the paths than you might expect.

We are not posting Lobster Claw, Lower Snowfields, and Little Headwall due to an overall lack of snow. On Sunday, Lobster Claw was virtually 100% bushwhacking. I think (and hope) this will change dramatically with the amount of wind loading taking place today. Please do not assume that the lack of a rating means there is no avalanche potential whatsoever. It’s your responsibility to make your own assessments.

In Huntington, the General Bulletin remains in place. I believe we will have widespread scouring through most of the gullies, but again, this does not mean that avalanche activity cannot take place. It’s probably a good time to wait it out a little bit, let the clouds clear and the winds die down, and then see what things look like.

Please Remember:

  • Safe travel in avalanche terrain requires training and experience. This advisory 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 the Harvard Cabin.
  • Posted 8:25 a.m. January 19, 2016. A new advisory will be issued tomorrow.

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

2016-01-19

Avalanche Advisory for Monday, January 18, 2016

This advisory expires tonight at 12:00 midnight.

Tuckerman Ravine has Considerable and Moderate avalanche danger. The Lip, Center Bowl, Chute, and Left Gully will have Considerable avalanche danger. Natural avalanche are possible, human triggered avalanches are likely in these locations. The Sluice has Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. The Lobster Claw, Right Gully, Hillman’s Highway, Lower Snowfields, and Little Headwall have no rating, due to the overall lack of snow in these areas; however, watch for signs of unstable snow in isolated steeper locations and larger areas of continuous snow.

Huntington Ravine is under a General Avalanche Bulletin. General Bulletins are issued when instabilities are isolated within forecast areas and are issued every three days or earlier if conditions warrant. Forecast areas in Huntington have less well developed bed surfaces for avalanches to run on. However, bed surfaces do exist, particularly in Central, Pinnacle, and Odell gullies. For today, expect wind slabs to develop in many areas. Winds will continue to strengthen tonight and remain very strong through Tuesday. As wind speeds rise towards 100mph, expect a significant amount of wind scouring to take place, eroding most, if not all, of the new snow from the gullies.

AVALANCHE PROBLEM: Wind slabs are the primary threat today. These currently exist in many locations and with the expected weather, they will be growing through the day. Expect an increasing hazard as snow falls and wind velocities rise today. The areas of greatest concern are in the headwall area of Tuckerman, such as the Lip, Center Bowl, Chute, and Left Gully. Any avalanche encounter is dangerous but the potential for traumatic injury increases due to the many small cliffs and boulders exposed by our thin snowpack.

WEATHER: A strong low pressure system well to our east will continue to send bands of snow showers to the the mountain. As the low strengthens and moves east, it will draw an arctic cold front across our terrain. This cold air mass will bring much colder air and high winds to Mount Washington and generate a protracted period of upslope snow shower activity lasting into Tuesday. This front has a strong squall line on its leading edge which may produce a brief but intense period of snow showers today. Expect winds to reach 75mph by sundown and near 100 mph tonight and into Tuesday. These strong winds, coupled with temperatures near 0F, will create challenging travel conditions today and tomorrow. 2-6″ of new snow is possible today.

SNOWPACK: We have been watching the avalanche terrain slowly fill in with snow, increasing the size of bed surfaces but are still well behind schedule in terms of a normal winter.  Even the forecast areas that now carry a five scale rating are discontinuous in nature and contain snowfields which, in the grand scheme of things, could be considered pockets of unstable snow. But even smaller slabs of snow can produce dangerous avalanches, especially in our steep terrain where the force of a sliding mass of snow combines with gravity to push people where they don’t want to go. Yesterday morning, we found fresh debris from two avalanches (Chute and Center Bowl) and then later there were two human triggered avalanches (Chicken Rock Gully, which is the small area left of Lunch Rocks and beneath the Lip, and Chute, a second time). Fortunately, these did not end in significant injuries but the outcome could have been very different.

New snow with increasing winds today will create new wind slabs which will have the classic “upside-down” structure to it. This creates a dangerous situation where a slab rests over lighter, weaker snow. We expect today’s wind loading to exacerbate both the previously existing slabs, which have probably been slow to stabilize, as well as the newly created ones.

Please Remember:

  • Safe travel in avalanche terrain requires training and experience. This advisory 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 the Harvard Cabin.
  • Posted 8:25 a.m. January 18, 2016. A new advisory will be issued tomorrow.

Frank Carus/Helon Hoffer, Snow Rangers
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2856

2016-01-18

Avalanche Accident – January 17, 2016

The following news release was issued by the White Mountain National Forest Sunday evening, January 17th. A more comprehensive accident summary and lessons learned will be posted later.

Two Climbers Trigger Tuckerman Avalanche

Early on Sunday afternoon, January 17, 2016, two climbers from Canada triggered and were caught by an avalanche in “The Chute” located in Tuckerman Ravine.

Just before 1 pm, the climbers ascended the couloir on the left side of the Ravine. Four other skiers and an avalanche class were nearby at the time. The pair of climbers reached the narrow point of the slope after climbing several hundred vertical feet from the floor of the ravine on a steepening slope. They climbed over an old fracture line a foot to a foot and a half high and continued into softer snow. After ascending approximately 30 more feet through deeper snow, the climber in front felt that the slope may be unstable and decided to turn around. As they turned to descend, the slope fractured about 75-100’ above them and approximately 75-100’ wide. The two climbers were carried most of the distance to the Ravine floor.  Two of the three nearby skiers were also caught and carried varying distances by the debris as well, while another skier below was able to dodge the debris. (see correction below)

One of the two climbers, Michel Houde from Lorraine, Quebec, sustained non-life threatening injuries and was treated and released by Snow Ranger staff and the Mount Washington Volunteer Ski Patrol. One of the skiers, Kaj Huld from Brunswick Maine, also received non-life threatening injuries. Members of several nearby avalanche classes assisted in transporting the second climber by litter to Hermit Lake where he was transported by snowmobile to Gorham EMS waiting in Pinkham Notch.

The Mount Washington Observatory reported 5.5” of snow on the summit during the previous day, with around 4” falling at Hermit Lake. Summit winds blew between 40 mph and 60 mph overnight from the west. Plumes of wind transported snow were visible in the morning as Snow Rangers made snowpack assessments. The wind shifted to the NW and diminished to 20 mph when visitors began to enter Tuckerman.

Each year from December 1st through May 31st, the US Forest Service is the lead agency coordinating SAR missions on the eastern side of Mount Washington which includes Tuckerman and Huntington Ravines.  The White Mountain National Forest operates the Mount Washington Avalanche Center to provide safety information and SAR services to the public.   The Avalanche Center had posted a General Bulletin Saturday Morning, January 16th ,on www.mountwashingtonavalanchecenter.org for the holiday weekend. A brief follow up analysis of the incident will be post on the website this week.

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Correction: the solo skier who is described as having “dodged the debris” was indeed hit and injured by the avalanche. In total, six people were in the path when it released. Only one was able to avoid being caught. Two of the five caught were injured. Broken down by group: of the two climbers who triggered the slide had one was injured; of the group of three, one escaped while the other two were caught, carried, and thankfully uninjured; there was also the aforementioned solo skier traversing his way low in the track toward Left Gully.

Human-triggered avalanche incidents

Synopsis: On Sunday, January 17, a wind slab avalanche cycle on the east side of Mount Washington occurred following a period of moderate snowfall and wind. Two human-triggered avalanches occurred, one of which was widely publicized on social media and in the news. A number of factors led to the incidents which are worth looking into in order to shed light on some of the issues around the events. As is the case with many accidents, it is easy to pick out poor decisions in hindsight. In reviewing incidents, it is also rarely productive assigning blame to individuals compared to what lesson can be drawn. This incident presents an opportunity to highlight what appear to be trends in travel practices and decision making on Mt. Washington.

Weather: The snowfall leading up to the avalanche cycle was a typical upslope snow event which often follows more robust synoptic systems passing through our region. As an air mass is forced up and over the windward side of the range, the cooling process turns lingering atmospheric moisture into snow. In the case of the Sunday, January 17 avalanche cycle, the synoptic storm system had deposited 8” on the mountain on the prior Tuesday and Wednesday. A period of unsettled weather followed with 2” falling Thursday and Friday accompanied by periods of high winds and prolonged low visibility. A natural avalanche cycle occurred sometime during this loading event with the areas beneath Center Bowl and Chute later showing debris piles. By the pre-dawn hours on Saturday, as a Nor’easter passed offshore to the east, snow began to fall again during a 4 hour period of light SE and SSE winds. This snowfall became the weak layer when the wind shifted to the west and increased to the 50 mph range. By Sunday morning, sky conditions were clearing with W wind speeds in the 50’s mph lifting snow plumes with the previous days 5.5” snow (.55” SWE) from the alpine elevations. These plumes were visible from the parking lot at Pinkham Notch in the early morning hours. By 10am cold temperatures and blowing snow had begun to give way to clear skies, sunshine, and light wind.

Avalanche activity: By late morning, skiers and climbers began to test the slopes in both Ravines.  Two skiers reported triggering a small slab (R1, D1) near Lunch Rocks beneath the Lip around 11am. One skier was carried about 20’ before arresting his slide. A little later, a guide entered South Gully in Huntington Ravine causing a slab to collapse and settle in place with no avalanche. At 12:50pm, an avalanche from the mid-section of Chute in Tuckerman Ravine caught and carried the two climbers who triggered the slide. Also caught were a solo skier crossing the runout on his way to Left Gully and two from a group of three skiers climbing up the track below the climbers. Of these five people caught and carried, two received minor injuries, with only one transported to a hospital. An avalanche course and a number of students were approximately 15’ from the moving debris on a 40 degree slope which had avalanched earlier in the avalanche cycle.

Chicken Rock Gully: SS-ASu-R1-D1, reported as 10-15cm deep, 15m wide, ran to elevation of the base of Lunch Rocks

A sub-feature in Tuckerman Ravine often referred to as Chicken Rock Gully.

A sub-feature in Tuckerman Ravine often referred to as Chicken Rock Gully. (image: MWAC, taken morning of Jan 17, 2016)

 

Chute: SS-AFu-R2-D1.5, estimated to be 10-50cm x 30m wide crown, 115m track of 400m path

The scene shortly after the avalanche in Chute. (image from Facebook)

The scene shortly after the avalanche in Chute. (image: from Facebook)

 

A view into the Chute after the avalanche. Crown most likely wraps around out of view to the right. (image: nealpinestart.com)

A view into the Chute after the avalanche. Crown most likely wraps around out of view to the right. (image: nealpinestart.com)

Analysis: We have been seeing both positive trends in avalanche terrain travel choices and decision making as well as trends leaving room for improvement. Unfortunately, the trends needing improvement are all too common.

First, for the positives:

  • Everyone involved was geared up appropriately for winter conditions with the right warm clothing, boots, etc. Despite the reputation Mount Washington has for “the world’s worst weather,” the number of travelers who come unprepared for the cold and wind is astounding.
  • Some of the individuals involved were equipped and trained to apply first aid skills to the injured. Similar to the increasing trend in avalanche education we are seeing, there appears to be an increased interest in becoming more self-sufficient in the mountains. While at times Tuckerman and Huntington Ravines seem like frontcountry recreation areas with Snow Rangers and caretakers at both Harvard Cabin and Hermit Lake, it is important to remember that these locales are indeed backcountry settings and help can often be a long way away.
  • Many of the individuals nearby, and one of the skiers who was in the path, were carrying avalanche rescue gear including beacons, probes, and shovels.
  • Several Level 1 avalanche classes were in progress in Tuckerman Ravine. More and more people each year are seeking out professionally-taught avalanche courses which is a very good thing.
  • At least some of the parties read the General Avalanche Bulletin issued on Saturday morning. This type of Bulletin is valid for up to three days, and was both in effect and posted Sunday morning. The Bulletin accurately described recent and upcoming snowfall and wind loading as well as the developed slopes which would become bed surfaces in this avalanche cycle.

Areas for improvement and lessons to take away:

  • Of the five people caught in the avalanche, none were wearing beacons or carrying avalanche rescue gear. Sadly, this is not that unusual in our terrain. The avalanche class was wearing beacons and carrying rescue gear, as was one skier who was able to get out of the path as well as the two skiers who triggered Chicken Rock Gully. Frequently, climbers leave behind avalanche rescue gear to save weight, leaving no quick course of action should burial occur. Hats off to all who recognize the value of carrying avalanche rescue gear to be searchable and have the committed discipline to carrying it. The gear may or may not save your life should you get caught, but it certainly won’t help you if it is in your closet. Situations change, plans change, and mistakes happen—always carry the gear.
  • Given the clustering of users near the Chute, it seems safe to assume that the Social Proof heuristic was at play. Following some discussion, the avalanche class chose to travel in steep terrain beneath a recently loaded slope. They were followed by the party of two climbers and the three skiers. Whether due to the easier travel following in someone else’s boot track, the erroneous assumption that a slope is safe because someone else already traveled on it, or the belief that other travelers know more than you, this behavior is all too common in Tuckerman Ravine. The two climbers then passed the avalanche class and ventured onto the unstable slope.  This bunching in avalanche terrain forces constant re-evaluation of hazard. Additional challenges exist when trying to rebalance risk on a continual basis based on actions of others outside your control.  This issue has been a factor in many avalanche accidents and fatalities locally, as well as around the world.  Mount Washington has very concentrated avalanche terrain and has a high amount of visitation.  We have seen on many occasions a group descend a route while others are unwittingly climbing up in the same avalanche path. This makes safe travel difficult when instabilities exist on a weekend on Mount Washington. Your party’s movements may be under tight control and stay within your chosen level of accepted risk, but only in the absence of other more unpredictable people.   Take the same scenario, with other people as an uncontrollable variable, and you may increase your risk rapidly.  This issue was demonstrated by this incident.  We often see a compounding effect of visitors concentrating together in unstable conditions when they should be considering staying clear of one another by using fracture limiting terrain features and avoiding runout paths.  This is certainly a major challenge for guided parties, courses and organized parties.  Managing objective mountain hazards like icefall, avalanches, crevasses, etc. is hard enough, but adding subjective hazards due to other parties may be untenable. Every leader must balance the group’s level of skill with their agreed upon risk tolerance on a constant basis
  • An associated concern to the above is the challenges of spreading out to reduce overall risk. While spreading out is a good, basic technique for traveling in or below avalanche terrain it may not be as effective as it is often assumed without a quality pre-plan to reduce risk. This pre-plan would review the actual benefits compared to truly going one at time, how you will communicate when spread out if new observations or decisions need to be made, and is this the best route.  A best route option should always be a constant question.  This can be a difficult decision because the safest route is often less convenient. Again, the effectiveness of spreading out as a team of 2 climbers, 3 skiers, or a large avalanche class are complicated when they are all interacting in the same terrain exposed to the hazards.
  • The two climbers overlooked a red flag when they climbed over a recently reloaded crown line and onto a slope that rises from 40 to 45 degrees or more. Moreover, all parties involved in the Chute incident crossed beneath this slope within 4 hours of a period of active loading. While everyone chooses their own level of acceptable risk, it is unclear whether all parties involved sought out the information needed to make an informed decision by reading the posted General Avalanche Bulletin or seeking the right weather data. Hourly precipitation and weather data can be found here and is included among the list of other useful weather related websites on our site. These sites can be incredibly useful tools in the planning stages of your trip or even in the field when cell access is available (don’t forget a pocket charger or spare battery).

Lastly, a short discussion of MWAC’s published products, and any avalanche advisory for that matter, is worthwhile. It is a valuable topic to expand upon specifically. See “Avalanche Products” in our website Blog, ‘The Pit’ this weekend for a more in depth discussion.

  • A General Avalanche Bulletin, which was published the day before these avalanche incidents, is used to convey hazards that are most typically a problem during the early and late season. This document is a one page narrative describing the hazards, but does not assign a danger rating. It is a broad discussion to highlight that instabilities and avalanche potential may currently exist, although not across the entire forecasting area in each Ravine.
  • It is a common occurrence across the United States to see active visitor use in avalanche terrain and have avalanche accidents before a 5-Scale Avalanche Danger Rating Advisory is utilized. These occur under either Informational Bulletins or no products. These isolated instabilities are acceptable and tolerated without postings due to the limited nature of the issues.  Incidents, although unfortunate, are a national actuality based on statistical probabilities and ever increasing backcountry use numbers. This fact clearly focuses to the importance of possessing avalanche knowledge and field skills.  This is an important reality to note when entering any avalanche terrain whether in the Eastern or Western United States.
  • Gaining and maintaining good avalanche assessment skills, training and experience is critical. If you don’t have this knowledge we would highly encourage you to get it through controlled learning environments versus relying solely on posted advisories.  As stated in our Bulletins and Advisories, it is merely one tool to make field decisions. This is not a disclaimer; it addresses the complexity and nature of avalanches and the inevitable spatial variability we often see.  If the Advisory states one thing and our dynamic weather creates another reality with increasing hazard, certainly go with your observations and neck hackles and not the advisory.  Your future well-being makes it essential that avalanche skills match your desire for playing in the mountains.  It will also help you draw as much as possible from the Advisory tool because we’ll be speaking the same language.

If you have any questions or comments feel free to contact us at mwactucks@gmail.com  We’ll do our best to respond in a timely manner.

Avalanche Cycle – January 17, 2016

20160117 Tuckerman Bowl

The Center Bowl and Lip area of Tuckerman. Snowfields are growing here and beginning to be active slide paths.

Helon and I got up into Tuckerman early this morning and were treated to the sight of two fresh piles of avalanche debris and one older pile. With our avalanche eyeballs wide open, we welcome the arrival of the 2015-2016 avalanche season. The recent slides were likely from overnight or early this morning, as they were both very soft and had slightly different levels of wind effects on the debris. The older slide was probably from earlier this week.

20160117 Chute

Looking up into the Chute variation, the narrows of the Chute is out of sight on the right. The crown was probably a couple feet deep or more in the center of this photo.

The first of the recent pair came from the Chute. We believe all the debris came from the crown lines visible in the picture, across the narrows of the gully, into the variation to the lookers’ left of the main path, and down along the buttress. Debris from this was approximately 2′ deep, some less, some more. The crown ranged in size from a few inches deep to a few feet deep.

20160117 Left side of Tuckerman

Two debris piles are visible, one above Helon and the other above and right of him. Crown lines are in the narrow sections of the Chute and far left side of the headwall.

The second of the pair was from the far left side of the Center Bowl, just to the lookers’ right of the Chute. The crown was still visible beneath the ice bulge, although wind loading was ongoing and working to fill it in. This slide was a little smaller than the Chute, with debris being about 12-18″ deep and a max crown depth of 18″ (just a guess, as we couldn’t access the deepest location and it had been partially reloaded.)

Even though we hadn’t yet begun using the 5-scale danger rating system, these new slides were not completely unexpected. We were a little surprised at the size; I’d call them both D1.5R1, but they are at the larger end of the R1 size. The one that surprised me a little is the older slide that crossed the hiking trail down low in the flats. The trajectory of this shows it coming from the Center Bowl and left side of the Center. Based on how far it ran in lean conditions and weather history, it was likely a pretty hard slab.

20160117 Debris in floor of Tuckerman

Avalanche debris in the floor of Tuckerman. The hiking trail is on the left side of this picture, under the debris. The extent of the tracks on this pile tell us that the slide happened before this weekend.

Here's clear evidence of an avalanche. These trees are flattened by the debris near the toe of the runout.

Here’s clear evidence of an avalanche. These trees are flattened by the debris near the toe of the runout.

After returning down to Hermit Lake, we got a report of another small avalanche triggered by a skier. This was in the area we call “Chicken Rock Gully,” which is the small terrain feature that fills in between the Open Book and Lunch Rocks, and from the top you can go right into the Sluice or Left into the Lip. The party triggered the slide near the rocks at the top of this slope. They reported that it was about 4-6″ deep, 40′ wide x 50′ long, and ran down to the bottom of Lunch Rocks.

Jeff Lane, Snow Ranger
Mount Washington Avalanche Center

Two human-triggered avalanches

Synopsis: On Sunday, January 17, a wind slab avalanche cycle on the east side of Mount Washington occurred following a period of moderate snowfall and wind. Two human-triggered avalanches occurred, one of which was widely publicized on social media and in the news. A number of factors led to the incidents which are worth looking into in order to shed light on some of the issues around the events. As is the case with many accidents, it is easy to pick out poor decisions in hindsight. In reviewing incidents, it is also rarely productive assigning blame to individuals compared to what lesson can be drawn. This incident presents an opportunity to highlight what appear to be trends in travel practices and decision making on Mt. Washington.

Weather: The snowfall leading up to the avalanche cycle was a typical upslope snow event which often follows more robust synoptic systems passing through our region. As an air mass is forced up and over the windward side of the range, the cooling process turns lingering atmospheric moisture into snow. In the case of the Sunday, January 17 avalanche cycle, the synoptic storm system had deposited 8” on the mountain on the prior Tuesday and Wednesday. A period of unsettled weather followed with 2” falling Thursday and Friday accompanied by periods of high winds and prolonged low visibility. A natural avalanche cycle occurred sometime during this loading event with the areas beneath Center Bowl and Chute later showing debris piles. By the pre-dawn hours on Saturday, as a Nor’easter passed offshore to the east, snow began to fall again during a 4 hour period of light SE and SSE winds. This snowfall became the weak layer when the wind shifted to the west and increased to the 50 mph range. By Sunday morning, sky conditions were clearing with W wind speeds in the 50’s mph lifting snow plumes with the previous days 5.5” snow (.55” SWE) from the alpine elevations. These plumes were visible from the parking lot at Pinkham Notch in the early morning hours. By 10am cold temperatures and blowing snow had begun to give way to clear skies, sunshine, and light wind.

Avalanche activity: By late morning, skiers and climbers began to test the slopes in both Ravines.  Two skiers reported triggering a small slab (R1, D1) near Lunch Rocks beneath the Lip around 11am. One skier was carried about 20’ before arresting his slide. A little later, a guide entered South Gully in Huntington Ravine causing a slab to collapse and settle in place with no avalanche. At 12:50pm, an avalanche from the mid-section of Chute in Tuckerman Ravine caught and carried the two climbers who triggered the slide. Also caught were a solo skier crossing the runout on his way to Left Gully and two from a group of three skiers climbing up the track below the climbers. Of these five people caught and carried, two received minor injuries, with only one transported to a hospital. An avalanche course and a number of students were approximately 15’ from the moving debris on a 40 degree slope which had avalanched earlier in the avalanche cycle.

Chicken Rock Gully: SS-ASu-R1-D1, reported as 10-15cm deep, 15m wide, ran to elevation of the base of Lunch Rocks

A sub-feature in Tuckerman Ravine often referred to as Chicken Rock Gully.

A sub-feature in Tuckerman Ravine often referred to as Chicken Rock Gully. (image: MWAC, taken morning of Jan 17, 2016)

 

Chute: SS-AFu-R2-D1.5, estimated to be 10-50cm x 30m wide crown, 115m track of 400m path

The scene shortly after the avalanche in Chute. (image from Facebook)

The scene shortly after the avalanche in Chute. (image: from Facebook)

 

A view into the Chute after the avalanche. Crown most likely wraps around out of view to the right. (image: nealpinestart.com)

A view into the Chute after the avalanche. Crown most likely wraps around out of view to the right. (image: nealpinestart.com)

Analysis: We have been seeing both positive trends in avalanche terrain travel choices and decision making as well as trends leaving room for improvement. Unfortunately, the trends needing improvement are all too common.

First, for the positives:

  • Everyone involved was geared up appropriately for winter conditions with the right warm clothing, boots, etc. Despite the reputation Mount Washington has for “the world’s worst weather,” the number of travelers who come unprepared for the cold and wind is astounding.
  • Some of the individuals involved were equipped and trained to apply first aid skills to the injured. Similar to the increasing trend in avalanche education we are seeing, there appears to be an increased interest in becoming more self-sufficient in the mountains. While at times Tuckerman and Huntington Ravines seem like frontcountry recreation areas with Snow Rangers and caretakers at both Harvard Cabin and Hermit Lake, it is important to remember that these locales are indeed backcountry settings and help can often be a long way away.
  • Many of the individuals nearby, and one of the skiers who was in the path, were carrying avalanche rescue gear including beacons, probes, and shovels.
  • Several Level 1 avalanche classes were in progress in Tuckerman Ravine. More and more people each year are seeking out professionally-taught avalanche courses which is a very good thing.
  • At least some of the parties read the General Avalanche Bulletin issued on Saturday morning. This type of Bulletin is valid for up to three days, and was both in effect and posted Sunday morning. The Bulletin accurately described recent and upcoming snowfall and wind loading as well as the developed slopes which would become bed surfaces in this avalanche cycle.

Areas for improvement and lessons to take away:

  • Of the five people caught in the avalanche, none were wearing beacons or carrying avalanche rescue gear. Sadly, this is not that unusual in our terrain. The avalanche class was wearing beacons and carrying rescue gear, as was one skier who was able to get out of the path as well as the two skiers who triggered Chicken Rock Gully. Frequently, climbers leave behind avalanche rescue gear to save weight, leaving no quick course of action should burial occur. Hats off to all who recognize the value of carrying avalanche rescue gear to be searchable and have the committed discipline to carrying it. The gear may or may not save your life should you get caught, but it certainly won’t help you if it is in your closet. Situations change, plans change, and mistakes happen—always carry the gear.
  • Given the clustering of users near the Chute, it seems safe to assume that the Social Proof heuristic was at play. Following some discussion, the avalanche class chose to travel in steep terrain beneath a recently loaded slope. They were followed by the party of two climbers and the three skiers. Whether due to the easier travel following in someone else’s boot track, the erroneous assumption that a slope is safe because someone else already traveled on it, or the belief that other travelers know more than you, this behavior is all too common in Tuckerman Ravine. The two climbers then passed the avalanche class and ventured onto the unstable slope.  This bunching in avalanche terrain forces constant re-evaluation of hazard. Additional challenges exist when trying to rebalance risk on a continual basis based on actions of others outside your control.  This issue has been a factor in many avalanche accidents and fatalities locally, as well as around the world.  Mount Washington has very concentrated avalanche terrain and has a high amount of visitation.  We have seen on many occasions a group descend a route while others are unwittingly climbing up in the same avalanche path. This makes safe travel difficult when instabilities exist on a weekend on Mount Washington. Your party’s movements may be under tight control and stay within your chosen level of accepted risk, but only in the absence of other more unpredictable people.   Take the same scenario, with other people as an uncontrollable variable, and you may increase your risk rapidly.  This issue was demonstrated by this incident.  We often see a compounding effect of visitors concentrating together in unstable conditions when they should be considering staying clear of one another by using fracture limiting terrain features and avoiding runout paths.  This is certainly a major challenge for guided parties, courses and organized parties.  Managing objective mountain hazards like icefall, avalanches, crevasses, etc. is hard enough, but adding subjective hazards due to other parties may be untenable. Every leader must balance the group’s level of skill with their agreed upon risk tolerance on a constant basis
  • An associated concern to the above is the challenges of spreading out to reduce overall risk. While spreading out is a good, basic technique for traveling in or below avalanche terrain it may not be as effective as it is often assumed without a quality pre-plan to reduce risk. This pre-plan would review the actual benefits compared to truly going one at time, how you will communicate when spread out if new observations or decisions need to be made, and is this the best route.  A best route option should always be a constant question.  This can be a difficult decision because the safest route is often less convenient. Again, the effectiveness of spreading out as a team of 2 climbers, 3 skiers, or a large avalanche class are complicated when they are all interacting in the same terrain exposed to the hazards.
  • The two climbers overlooked a red flag when they climbed over a recently reloaded crown line and onto a slope that rises from 40 to 45 degrees or more. Moreover, all parties involved in the Chute incident crossed beneath this slope within 4 hours of a period of active loading. While everyone chooses their own level of acceptable risk, it is unclear whether all parties involved sought out the information needed to make an informed decision by reading the posted General Avalanche Bulletin or seeking the right weather data. Hourly precipitation and weather data can be found here and is included among the list of other useful weather related websites on our site. These sites can be incredibly useful tools in the planning stages of your trip or even in the field when cell access is available (don’t forget a pocket charger or spare battery).

Lastly, a short discussion of MWAC’s published products, and any avalanche advisory for that matter, is worthwhile. It is a valuable topic to expand upon specifically. See “Avalanche Products” in our website Blog, ‘The Pit’ this weekend for a more in depth discussion.

  • A General Avalanche Bulletin, which was published the day before these avalanche incidents, is used to convey hazards that are most typically a problem during the early and late season. This document is a one page narrative describing the hazards, but does not assign a danger rating. It is a broad discussion to highlight that instabilities and avalanche potential may currently exist, although not across the entire forecasting area in each Ravine.
  • It is a common occurrence across the United States to see active visitor use in avalanche terrain and have avalanche accidents before a 5-Scale Avalanche Danger Rating Advisory is utilized. These occur under either Informational Bulletins or no products. These isolated instabilities are acceptable and tolerated without postings due to the limited nature of the issues.  Incidents, although unfortunate, are a national actuality based on statistical probabilities and ever increasing backcountry use numbers. This fact clearly focuses to the importance of possessing avalanche knowledge and field skills.  This is an important reality to note when entering any avalanche terrain whether in the Eastern or Western United States.
  • Gaining and maintaining good avalanche assessment skills, training and experience is critical. If you don’t have this knowledge we would highly encourage you to get it through controlled learning environments versus relying solely on posted advisories.  As stated in our Bulletins and Advisories, it is merely one tool to make field decisions. This is not a disclaimer; it addresses the complexity and nature of avalanches and the inevitable spatial variability we often see.  If the Advisory states one thing and our dynamic weather creates another reality with increasing hazard, certainly go with your observations and neck hackles and not the advisory.  Your future well-being makes it essential that avalanche skills match your desire for playing in the mountains.  It will also help you draw as much as possible from the Advisory tool because we’ll be speaking the same language.