Mar 012015
 

This advisory expires tonight at 12:00 midnight.

Tuckerman Ravine has Moderate and Low avalanche danger. The Sluice, Lip, Center Bowl, and Chute have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. All other forecast areas have Low avalanche danger. Natural and human triggered avalanches are unlikely in these locations.

Huntington Ravine has Low avalanche danger. Natural and human triggered avalanches are unlikely.

AVALANCHE PROBLEM: Persistent Slabs are the primary threat again today. You’ll find this in the Moderate rated areas of Tuckerman. Numerous layers at varying depths have the potential to release as large hard slab avalanches. Areas rated at Low danger generally have been scoured clean of any new slab, leaving behind firm and stable snow. Although these locations do not have superb skiing or riding conditions, they pose much less risk than slopes rated Moderate.

New snow is expected to begin this afternoon. If you are on the mountain well after dark, avalanche danger may increase above today’s ratings due to the development of fresh wind slabs.

WEATHER: High elevation clouds have already begun to appear and these will thicken and lower through the day. We are expecting a light snowfall across the area tonight, with upslope enhancement in the mountains adding to the total amounts. You can expect 1-2” in the valleys, but in the mountains possibly 2-4” by tomorrow morning with additional upsloping snowfall during the day Monday. For today, winds will be generally from the west and increasing to 35-50mph.

SNOWPACK: Areas rated Low are pretty easy to describe…they are firm older snow that has been scoured or wind-packed into a very stable surface. As mentioned, this may not provide the best skiing you’ve ever experienced. I’d recommend crampons and an ice axe or whippet for the ascents, and that should say something about the snow quality. But as many people yesterday learned, the snow is firm but not icy in these areas.

Locations rated Moderate will force you to either a) ignore the fact that avalanches can cause serious injury or death, or b) calculate a risk vs benefit analysis for the snow you want to get onto. I watched yesterday as a couple people chose “option a.” One skied the Lip without any firsthand info about the snow in this area. The other watched as I dug a pit and made my decision to not ride the slope, then he skied it anyway. For me, and hopefully for you as well, you will recognize that the slabs in Moderate rated areas fit the “low probability-high consequence” description. This type of snowpack is difficult for a person to trigger—at least you might think so right up until the point when it releases, then you might think otherwise. Most likely trigger points will be locations where the slabs are relatively thin, such as near buried rocks, under areas that had previous avalanche activity, or near the edges where the wind slabs taper down. In your risk-benefit analysis, know that if you trigger an avalanche, it will probably be a high consequence large hard slab avalanche. Your reward for taking the risk will be a couple inches of softer snow on top of 1F-Pencil hard slab. For me yesterday, the reward was not great enough to warrant taking the risk. Do your own stability assessments of the snow you want to experience, and make informed decisions.

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 8:00a.m. March 1, 2015. A new advisory will be issued tomorrow.

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

2015-03-01

 Posted by at 7:58 am
Mar 012015
 

In this morning’s advisory I wrote briefly about the decision making of two individuals who skied the Lip Saturday afternoon. I’d like to expand on this commentary, in order to provide a little more context, but primarily because I think what I observed is unfortunately too common, yet easy to avoid these same behavior patterns. Here’s what was written in the advisory:

“Locations rated Moderate will force you to either a) ignore the fact that avalanches can cause serious injury or death, or b)calculate a risk vs benefit analysis for the snow you want to get onto. I watched yesterday as a couple people chose “option a.” One skied the Lip without any firsthand info about the snow in this area. The other watched as I dug a pit and made my decision to not ride the slope, then he skied it anyways…Your reward for taking the risk will be a couple inches of softer snow on top of 1F-Pencil hard slab. For me yesterday, the reward was not great enough to warrant taking the risk. Do your own stability assessments of the snow you want to experience, and make informed decisions.”

First, I wholeheartedly stand behind the concept of individuals being responsible for their own actions and decisions. With very few exceptions, the Forest Service doesn’t officially make terrain “open” or “closed” to skiers, climbers, or hikers. Instead, we strive to collect and analyze information, and make this available in a useable format to help people make informed decision. In my opinion, this is just the way it should be. You’ll rarely find me stating that what someone did was a mistake, a stupid thing to do, or that they’d pushed it too far. Instead, you’ll often hear me talk about alternatives that may have been safer, conservative decisions, and tolerance for risk.

How one perceives risk is very individualized. For example, there are people (e.g. my own mother) who think I’m a crazy daredevil for intentionally spending time in the mountains in winter, let alone that I regularly go into avalanche terrain when conditions may be unstable. To her, it is simply easy to say that people shouldn’t be doing this sort of thing. From my perspective, I view my decisions and actions relative to winter and avalanches as conservative. Since I began my journey with avalanches and snow science, I’ve seen enough accidents and triggered enough avalanches to know that I need to listen to the voice inside by head that leads me toward safer slopes. I think my regular ski partners can attest to the fact that this does not mean I am unwilling to ride in conditions with less than ideal stability, it just means that I have developed my stability assessment skills in conjunction with a conservative mindset in hope that I am significantly reducing my uncertainty and residual risk after I have collected all the information I think is necessary.

So, let’s say we can agree that traveling in avalanche terrain (when stability is less than very good) does carry some inherent risk. We can also agree that we can collect information to help us understand the potential avalanche character, the likelihood of triggering, and the potential consequences of a release. Further, we can agree that there is nothing we can do that removes the risk 100% from traveling in this terrain under these conditions, i.e. there will always be some level of residual risk. If we can have these agreements, then we can begin to understand how different people can willfully engage in the terrain in different manners. There will always be some people who think it’s too dangerous to be on a slope with any avalanche risk, and there will be others who roll the dice a little more in marginal conditions. Of course, there are many people who fall somewhere in between.

So if you’re following me so far, this is where I want to get into yesterday’s observations. My party of three was heading up into Right Gully, knowing the stability there is very good. I wanted to get my hands into the snow under the Lip to see if this might be a reasonable second objective, so I headed up under the Sluice and angled left into the lower part of the Lip. My partners came over to a safe location where they could keep an eye on me as I worked up into the Lip. I found a firm snowpack with several layers and interfaces sitting on top of the pencil+ hard slab that developed during intense winds on February 16th. In my one compression test, I got the slab to fail at 12 taps (CT12 or CTM, Q1). At this point, I already had formed an impression of the snow being firm and not very likely to trigger under the weight of smooth skier, but that an impact or a weak point could be enough to create a large slide. The quick pit I dug confirmed this a little further. To add complexity to the decision, there were nine people in three separate parties down in the floor of the ravine. If an avalanche were triggered and if it were large, it could reach one or more of these parties. Again, the uncertainty principle came up in my mind. How could I be sure an avalanche would not run that far? Well, I couldn’t.

We decided to climb slightly higher, regroup, and ski down from there. As I was working my way up from the pit about 100’ higher, I began to find an ice crust under the relatively shallower snow. This was enough to make that voice in my head speak up a little louder. It was telling me that the quality of what I was about to ride was good but not all that great, so why not play it safe? At this time, low drifting snow began to unexpectedly pour over the Lip area. This snow turned into small chunks, then to bigger chunks. It quickly dawned on me that there was a skier about to drop into the Lip above me, and my partners were unable to see this in advance from their location. I retreated to my right to put some more distance between me and the slab, and he skied the slope gently and without incident.

My group backtracked and ascended Right Gully. At the top, one from our group, a friend of my friend, decided he would ski the Lip as well. Without much more discussion he took off in that direction. My friend and I decided to go for the steep and technical left fork of the Lobster Claw. We had a good run down and rejoined the third in the floor of the ravine.

I had some time last night to think back on how things played out, and there is one piece that troubles me about the day, and it applies to both skiers who rode the Lip. It’s not that they skied a slope that was unreasonable from a stability perspective. In fact, I’m not at all surprised that nothing happened. I think people could have skied it all day without triggering the slope (although that does not imply total stability or safety.) The troublesome part, as I see it, is the amount of information these two people had prior to getting onto the slope.

I didn’t talk to the first skier, so I have to make some assumptions. I believe he climbed up through Right Gully, then skied the Sluice before climbing back up Right and heading over to the Lip. I can confidently say that no one had done any snow assessments in any location that would have been representative of the snow in the Lip. Even the snow in upper part of the Sluice would not adequately represent the slab in the Lip, but in the Sluice there were only ski tracks, not anything that indicated anyone had done any kind of stability assessment. So what information did he possess that helped him make an informed decision? If he read the advisory, he would have had a reasonable accurate picture of the avalanche character and likelihood. Above and beyond that, he could have had were visual clues from the floor. He could also have had a long history of skiing in Tuckerman, in which case he’d probably be well aware that the Lip and Sluice are two of the most active avalanche paths even when everything else is as stable as it gets.

The second skier, who was with me as I did a quick assessment, had a little more information available to him. He had the visuals of the surface snow, he watched the first skier descend, and he saw the pit that I had dug and talked with me about my thoughts. He knew the snow in Right Gully wasn’t ideal for skiing, and he suspected that the snow in the Lip would be better. For him, the snow looked good enough to take on what I’d described as a “low probability-high consequence” slope. For me, the decision was the opposite. I think this is due to a number of factors, including differences in our goals, differences in our commitment levels and efforts in getting to this terrain, and largely to my history of being intimately experienced with avalanches accidents and their aftermath.

I mentioned above that I don’t often say that someone made a mistake. I think in this case I’ll go out on a limb and say that mistakes were made. Fortunately, this mistake didn’t cost anything because the slope was stable enough to not avalanche under their impacts. The mistake that I see that both these skiers made was in how much information they gathered to aid their decision making process. I won’t speculate as to why they decided to ski what they did, because really no one besides yourself can truly know what motivates you. But I can tell you that both skiers passed up readily available information.

In the case of the first skier, this is not the first time I’ve seen this pattern from him, which leads me to wonder if he’s developing a sense that Moderate-rated slopes are reasonable, but this is speculation again. In avalanche terrain, information can be gathered in many different ways. My approach yesterday is one alternative; however, it did put me at risk when the first skier came in above me. Climbing up from the bottom often can be done safely, but not always, so I won’t say you should always approach from below. Sometimes it’s a better idea to approach the snow from the top of a slide path, in the actual avalanche starting zone. Sometimes you will want to stay away from the slope entirely until you have more information.

If you look at the entire amount of time put into a trip up Mt. Washington for a couple runs, the time it takes to do stability assessments need not be a lot. That first skier could have spent less than 30 minutes to access the snow in the Lip, do some assessments, and then decide to ski it. It’s not the decision to ski that was the mistake, it was the lack of information related to snow stability. The reason why I say these skiers chose “option a”, ignoring the fact that avalanches are dangerous, is that without sufficient information, a risk assessment becomes useless. Or perhaps the truth is somewhere in between, in that the skiers do indeed know that avalanches are dangerous, but maybe that they didn’t care about the dangers or don’t think it will happen to them. I won’t ever truly know.

Here are my take-home points from this…When you’re going into avalanche terrain, there are a few things you should always do. First, read the advisory. Don’t just look at the slatboard for a rating level; find out what the issue is and try to understand it. Second, gather as much information as you can or as you need along the way. Sometimes it doesn’t take much to tell you not to go skiing steep slopes. Other times you need to look hard for more information. Seek information that contradicts your beliefs, as opposed to our natural tendency to seek information confirming your beliefs. Third, consider your goals and your alternatives, and don’t be afraid to choose less risky routes. If you find yourself leaning toward a slope that might have stability problems, consciously examine the benefits in light of the potential consequences. Ultimately, you need to own your decisions. Engagement in avalanche terrain is a personal choice, so if you aren’t ready deal with the risk and consequences, you have the ability to stay away until the conditions improve or you are ready to meet the challenge more safely.

Thanks for reading,

Jeff

 Posted by at 7:29 am