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For those of you recreating in a deep, stable snowpack, the words “scary moderate” go together as improbably “donuts” and “wellbeing.” Ski with any frequency in the shallow and pissed-off snowpack of the Rockies, though, and chances are you have some idea what scary moderate means.
For those of you recreating in a deep, stable snowpack, the words “scary moderate” go together as improbably “donuts” and “wellbeing.” Ski with any frequency in the shallow and pissed-off snowpack of the Rockies, though, and chances are you have some idea what scary moderate means.
And therein lies the rub, as they say. The term suggests something; it’s shorthand for a broader concept. In many situations, this is just fine. We use shorthand labels all the time. Sketchy dude. Tweaky knee. Gloomy day. I get it.
The problem with scary moderate is that misunderstanding the concept or not fully thinking it through is the first step in getting myself killed while skiing. In truth, it hints at something we should all understand on a deeper, fundamental level. So I say to you — banish the term from your limitless intellect and abundant vocabulary!
CMAH
If you’re spending your workday surfing WildSnow (stickin’ it to The Man!), then I trust you’re familiar with the North American Danger Scale — the green-yellow-orange-red-black scale rating avalanche hazard into five levels: low, moderate, considerable, high, extreme. We can debate the nuance and merits of the scale itself (that’s another post or two entirely), but let’s stick with what we have.
You might know most forecasters in the United States and Canada rely on an academic paper, “A Conceptual Model of Avalanche Hazard,” (CMAH), first discussed at the International Snow Science Workshop in 2010, as the foundation for creating their daily forecasts. (It’s easily retrievable online, so click through or track it down if you’ve not read it.)
The North American Danger Scale.
Reading the CMAH paper will greatly increase a user’s understanding of danger ratings and how forecasters arrive at them. Integral to this understanding is recognizing the danger rating on the day is merely one component — and probably not the most important component at that — of the day’s forecast.
In addition to the danger rating, of course, we have:
-nine “avalanche problem types”
-the likelihood of triggering (distribution of the problem x sensitivity to triggering=likelihood)
-destructive potential
-and location.
In summary, we have the danger rating, the overall avalanche problem capturing the above bullet points, and the textual description.
Simple, right?!
Not So Fast
Putting all these factors together while tracking weak layers over time, and updating the forecast with the latest meteorological events on a daily basis makes for a complex task. There is no quantifiable formula, either — ultimately the forecasters must make a final, subjective call on the forecast.
Consider likelihood as a range of probabilities. Moderate, for example, means natural avalanches are unlikely, and human-triggered ones are possible. Considerable, or level 3 or orange, indicates naturals are possible and human-triggered are probable.
Possible versus probable? There’s quite a range of likelihood within those descriptors, a good dose of uncertainty already complicates the danger rating. Add to this location, destructive size, and other subtle factors like the timing of a storm, for example, and it’s a maddening task to arrive at any sort of simple forecast on the day. And then do it again tomorrow. Still interested in that forecasting job?!
Avalanche Problem Types
Luckily for us, perspicacious academics and visionary mountain pros give us another means to make sense of the forecast, as long as we’re listening. The nine “avalanche problem types,” broken into three main categories, allow us to derive more context from the bulletin.
“Storm” problems — loose dry, wind slab, storm slab — are generally present during or immediately after … you ready? A storm. Woh! This is easy!
“Wet” problems — loose wet, glide cracks, wet slab — are usually associated with … drum roll, people, warming, and rain. Ding-ding-ding, we have a winner! Hot damn, I’m getting good at this.
And lastly, you won’t believe this, but “persistent” problems (deep-persistent slabs and persistent slabs) form in old snow and tend to hang around for a long time … they persist in the terrain. And didn’t I say this was complicated? It sounds so simple!
Cornice falls … you noticed I missed one, eh? I’ll let the hive debate whether or not cornices are most associated with storms or wet problems, but you can probably argue it either way. I’d go wet, personally, but those things tend to grow and fall off during prolonged, stormy wind events, too, so take your pick.
But What About Scary Moderate?!
So the CMAH incorporates a bunch of elements to arrive at a forecast and a danger rating. Still, If you’ve read the paper and/or understood my blathering thus far, you can see that simply saying “it’s a moderate” day or answering “considerable” when your buddy asks what the danger rating is, misses crucial information contained in the full forecast.
A recent accident and fatality involved a group receiving only the danger rating and avalanche problems on the day — the textual description was not communicated to the group, and in the end, they triggered an avalanche in terrain described in the bulletin. The text portion of the forecast on the day of the 2013 Sheep Creek accident (six involved, five killed) perfectly described the terrain in which the avalanche occurred.
In short, understanding the forecast requires understanding the danger rating, the problems, and reading/digesting the textual information, too.
Something deep and persistent lurked in Upper Cheap Scotch creek, near the Sorcerer Lodge in BC.
And at long last, we’ve come full circle to scary moderate. Scary moderate typically describes a “low-probability, high-consequence” situation like an avalanche bulletin involving a deep-persistent slab. Chances are you won’t trigger it, but if you do, you’re probably done for.
(Some forecasters use the term “spooky moderate” in a slightly different context, just FYI. That’s another rabbit hole for another time. And for a professional’s take on scary moderate, check out Brian Lazar’s excellent blog post here.)
So why isn’t the danger rating considerable or high when people might get killed in avalanches? Remember that CMAH involves likelihood — how widespread is the problem and how sensitive to triggers is it?
As a persistent weak layer gets buried or begins to heal, the likelihood of triggering goes down, but often the destructive potential goes up. A layer of facets buried 20cm deep can only produce a relatively small avalanche. Get another 150cm of snow on top of that and it might start to heal slowly and my svelte little body (read: puny and weak) has less chance of triggering it, but if I do manage to trigger it, there’s a bunch more snow available to slide down the slope and bury, injure, or kill me. Lower likelihood of triggering, but larger destructive potential. Scary.
Recall, too, that there’s no simple formula for determining the overall danger rating. Forecasters don’t assign a number to each component, for example, and then simply total them to arrive at a danger rating.
Rather, they determine the danger rating only after considering likelihood, size, and location. So a moderate rating with wind slabs is a far different beast than a moderate rating with a deep persistent slab. One is easy to predict and avoid, while the other is difficult to predict, hard to identify in the terrain, and fails in surprising ways.
OK, Get to the Point, Dude
The punch line? The point of all this virtual caterwauling?
People use scary moderate as a shorthand for these low-probability/high-consequence events, and for some of us, it works. My hesitation is if the average backcountry user or avy instructor uses the term, it overemphasizes the danger rating to the detriment of appreciating the problem on the day and the nuance in the rest of the forecast. Saying “scary moderate” as shorthand for what should be a deeper discussion sets that person up to treat all moderate days the same … which they most certainly are not.
Understanding that several different situations can lead forecasters to call the day moderate primes us to go beyond just the day’s rating/color/level. Just as we don’t use a beacon without a shovel and a probe, perhaps we should normalize including the problem and “bottom line” of the forecast when mentioning the danger rating. Danger-problem-text. Beacon-shovel-probe.
For example, if we keep the CMAH in mind, we recognize that a deep persistent problem that’s very difficult to trigger, but might produce a size 4, could qualify as a moderate day (low likelihood, super-high consequence, isolated on certain features). The same forecaster, under different conditions, might also call a widespread, super-sensitive windslab only producing size 2’s moderate, as well—same forecaster, same danger rating, vastly different situation.
I certainly don’t mean to imply the danger rating comes down to one kook in the office, all her biases at play, and excessive uncertainty. On the contrary, I know the Colorado folks have a state-wide video conference each morning, so the entire team can arrive at a consensus, address blind spots, and in the end collaborate on the forecast. There are a bunch of checks and balances built into the system — but to be sure, the system is not a mathematical formula or immune to subjectivity.
Isolating a weak layer in the snowpack.
So the bottom line, for me, becomes whether or not we non-forecasters should be throwing around shorthand terms like scary moderate? I tend to avoid using it on avalanche courses and in writing, simply because it denies the reader or student a deeper understanding of what it entails.
If the Norse god of hunting and snow, Ullr, made me king of the backcountry or even better, an Instagram influencer, I would banish the term from Facebook groups, level 1 avalanche courses, and skintrack banter amongst bro-gnars.
But with an audible sigh of relief from the readers of Wild Snow I am not a king, nor any sort of influencer, but merely a middle-aged mountain guide with a bit of a muffin top and the occasional soapbox from which to deliver febrile rants directed at an audience of people wishing they were out skiing instead of internet’ing.
So take my advice for what it’s worth. It’s nothing more than a non-binding suggestion to at least consider uttering the term scary moderate in a select crowd, one that understands the shorthand you’re using.
Rob Coppolillo writes articles, blogs, and books from his home in the Pacific Northwest of the United States. He’s also an internationally licensed mountain guide and the owner of Vetta Mountain Guides. Connect with him @vettamtnguides on Instagram or here in the comments.
Rob Coppolillo is a mountain guide and writer, based on Vashon Island, in Puget Sound. He’s the author of The Ski Guide Manual.
36 comments
Thanks for posting this Rob. Its a point well taken and I will try to refrain from using it. I could take it one further and when I hear it thrown around (which is very often in Colorado) I could ask “what is the danger, problem and text that makes it spooky?”.
Probably a problem for another post, but it really bums me out that we use 5 colors. Sadly as this post reveals 5 colors isn’t enough and maybe we should increase it to 7 or 10? I guess the complexity of colors stems from the belief that there can be snow “science” or avalanche “experts” and they need something more “nuanced”. However, forecasting tools are wildly encourage to be used by the masses without science or expertise. It seems like if that is the case then traffic light colors could get it done and keep it far simpler. Green would be the same “low”, yellow would only work for regular old moderate and the break to red could start at “spooky moderate” and above. It would then be up to the reader of the forecast to infer if the red was worth rolling the dice with lives on the line.
brudda!
i’ve had a smarter-than-me professional argue for reducing the scale to four colors! woh! then at least orange/con/3 would be in the top half of the scale …
when you out here next? let’s continue the discussion in person!
I’m definitely not smarter that you, but I’ve argued for a 4 color scale for a couple years now. Until everyone recreating in avalanche terrain has our education elevated to the level of understanding exactly the concepts you discuss here, and we read the full discussion, and we apply throughout our day, a lot of us will continue to default to the color scale. And unfortunately, as was shown in a really interesting study a couple years ago, most recreationists divide up that danger scale into 5 equal hazard chunks which puts “considerable” right in the middle where it’s interpreted as not so bad. When in fact most of the more avalanche-educated users recognized the scale as more of an exponential increase. Functionally, I don’t think there’s much use for black. For those rare black days, just use bold all caps in red and say “really, just stay home” or something.
Better yet, let’s take those colors out of the picture entirely. When we see red as high danger, it’s easy to fall into the trap of letting both considerable and moderate AND the grey area in between, seem a lot less dangerous. Which to a point, they are. But I always worry it leads to a false sense of security and a dumbing down of the danger rating at hand. I’d assume with no colors, users may be a bit more inclined to read the forecast rather than “green lighting or red lighting” the day.
I find this insights especially interesting:
[The three] traffic light colors [green, yellow, red] could get it done and keep it far simpler.
Green would be the same “low”.
Yellow would only work for regular old moderate.
And the break to red could start at “spooky moderate” and above.
It would then be up to the reader of the forecast to infer if the red was worth rolling the dice with lives on the line.
—–
I’d also like to see a different word used for the “yellow rating”, rather than “moderate”. Maybe “Caution”?
Drive-In Control dot org states: “The flashing yellow light means: ‘proceed with caution.’ ”
https://www.driveincontrol.org/yellow#:~:text=The%20flashing%20yellow%20light%20means,Who%20It's%20For
Dang, pretty much nailed it
If you, the BC user understand:
Danger scale;
Avy problem;
And appropriate mitigation measures/ terrain management;
Then all good with status quo…..
How about the avy forecast re- defining danger scale not to natural vs artifical trigger- ability, but:
Likelihood of mortality- Death potential- consequence relevant and risk for us recreation knuckleheads????
Ah, maybe you’re on to something — the bulletin includes “size,” which is of course strongly correlated with death potential, but another scale perhaps? A stack of skull-and-crossbones, indicating “lethality scale”?!
I hope you’re slaying, wherever you are, JMO!
Pretty new to the avy world (took level 1 two years ago), and definitely see how the shorthand language could lead to or perpetuate shorthanded understanding. Coming from kind of a different angle on things though, as someone who lives close to the San Juans I do like the term to the extent that it regularly reminds me to be scared of the problem. It’s been weird over the past two winters going from a snowpack last year that got a lot of people killed skiing 30-35 degree slopes on scary moderate to considerable days, to a snowpack this year that was weirdly lacking in persistent problems (at least for a portion of midwinter). It’d be unfortunate to let a year with less persistent issues alter my judgement in future years with more persistent issues. So the term just feels like a nice reminder at times that I really should be scared of persistent problems where they exist and that it’s a solid call to not play games with those layers.
Brother Ben — Try moving to the Pacific Northwest … talk about a mind-warp!
Great points and if you’re getting something out of “scary moderate,” then hot damn, keep using it. I just get heartburn when I hear people say “scary moderate” and then a bunch of heads nod … my worry is that a portion of those bobbing heads don’t really get it and are just agreeing …
Sounds like the Juans have had a great season and the West Elks even better! Lucky you!
I definitely experienced that myself when starting to learn about avy safety – you finally start to get a sense of how the ratings work, and then randomly get exposed these terms that put a vaguely defined twist on the ratings, and a sort of cultural expectation that you know what it means (even though you don’t). While I do like the vibe that scary moderate gives off, it’s pretty unhelpful if it goes undefined and is just the common lingo bouncing around town. From a confused newbie perspective, I found various podcasts discussing/debating danger ratings in detail to be extremely helpful in figuring the lingo out and getting a sense of how relate the forecast to what level of danger I want to expose myself to.
Yeah, I wish Krause were still doing his podcast, for sure! The Avalanche Hour seems great — that’s Caleb’s, yeah? Whatever the case, sounds like you are “getting it” — good on ya!
Besides the discussed low probability high consequence dangerous moderate conditions, I’ve thought about those moderate days where there’s widespread touchy storm or wind slabs as “scary” as well. Maybe the forecast gets it wrong. One thing I remember from my avy 1 is my instructors saying it’s always ok to increase your rating of the danger.
Seems to me like the issue has to do with human nature, not avalanche likelihood. If the forecast for a zone is Considerable for 2-3 months at a time, risk fatigue will set in for backcountry users. In places like the northern Front Range the risk SHOULD be considerable a lot more often.
Avalanche risk is inherently unpredictable-forecasts are great at giving an idea of snowpack in broad brushstrokes, but not for a specific location. We (as a species) just aren’t wired for that level of randomness.
After more than one scary incident on moderate days, I just play it as safe as given terrain allows-and still accept that I could be killed. That’s the reality we want to ignore.
I don’t have a systematic answer for how to convey the actual risk of backcountry skiing. I don’t think spooky moderate is a good rating-the number of people who die when that’s the avalanche forecast indicates that those days are actually really dangerous-that’s not what the moderate rating (spooky or not) conveys.
Yeah, Macie, the term leaves me a little uneasy, too … and I, like you, have no easy answer for it!
After listening to a UAC podcast interview with Grant Statham I read CMAW and found it really helpful to better understand forecasting application in a recreational context. I totally agree with a thrust of this article, and am working to apply the nuances of the CMAH including avalanche problem and size, distribution and sensitivity as great way to organize and target recreational field observations and application of broad forecasts to micro nowcasts. I recently made my own laminated checklist cheatsheet built from the AIRE model and additional factors info you present in the Ski Guides Manual, and added shortened sheets for the CMAW with full descriptions of the avalanche problems.
Grant is no dummy, that’s for sure! He’s a big thinker on this kind of stuff. Thanks for buying the book and let me know how the cheatsheets are helping you!
Hey Rob, thanks for questioning a widely used (and taught) phrase. If we’re nitpicking language though (and I’m a nitpicker), I take issue with your use of “probable” in “Considerable, or level 3 or orange, indicates naturals are possible and human-triggered are probable. Possible versus probable?” I encourage students to eliminate “probable” from options of likelihood and substitute “likely”, simply because probable sounds too much like possible and starts with the same letter ‘P’. Unlikely. Possible. Likely. Very Likely. Certain (or Near Certain, whatever). Those are the CMAH options and I’m glad we don’t have more to get sucked into the weeds with. Plus, when I record problem, location, likelihood and size in my field book, I can abbreviate likelihood by the letter rather than having to write it out. Very laborious, ya know.
I’m also all for dropping “extreme” from the 5 point scale to a 4 point. If it’s a historic cycle, that’ll come up in the bottom line and the associated avalanche warning. Con/orange/L3 being in the top half of the scale rather than the exact middle sure makes sense to me.
Probable and possible! Great point — I’m going to do my best to stick to Likely … hold me to it!
Too much information can lead to an inclination towards complication.
Let’s not outsmart ourselves.
Seems like our lives used to be not enough info (ignorance), while these days it’s usually too much info — which makes the challenge competence in integrating it, putting it through a process. On balance, though, I’ll err on the side of too much info, rather than too little!
I think the challenge with the CMAH scale is that the threshold for the higher rating/color increases as the rating color increases. This reminds me of an exponential scale, such as how earthquakes are measured, i,e, an 8.0 seismic event is 100 times stronger than a 7.0 event and a 7.0 is 100 times stronger than a 6.0. Translated to avalanches, we know extreme events are short lived (and a small percent of days over the entire season) and often reserved for the biggest storms and most dangerous setups, followed by a period of high, considerable, and then we end up with with the danger moderating substantially (according to the scale at least) as time progresses. And therefore we spend the majority of days over the course of the winter in the moderate rating that includes all those lingering issues from the last High or Considerable event. I love the Utah Avalanche Center’s avalanche rose graphic for this reason, it gives you a good idea of where the danger increases, and also keeps you aware of what the next compass direction over, or elevation band is with regards to your plans for the day.
Good thoughts — interesting that most (all?) other avy centers in the States have gone away from the Utah-style graphic. That’d be a worthy article in and of itself!
Great article Rob and a great discussion. When persistent slab conditions exist I generally stay out of the steep, high altitude terrain and the “danger prone” exposures. I think your spot on, “scary moderate” may be an ok term for us talking to our buddies that we’ve been skiing with for 20 years, but it probably does not belong in an educational setting. My opinion only; when dangerous, unpredictable persistent conditions exist under a moderate warning, forecasters might want to consider calling those day considerable. We should always remember, its a danger scale. If death is probable, is it not wise to consider things to be more dangerous?
Indeed, this is a fierce debate — con vs. mod on certain days. There are a bunch of ways to end up at one or the other, distribution, likelihood, etc … I don’t envy the forecasters on days like this!
I’d also like to see a different word used for the “yellow rating”, rather than “moderate”.
Maybe “Caution”?
Drive-In Control dot org states: “The flashing yellow light means: ‘proceed with caution.’ ”
https://www.driveincontrol.org/yellow#:~:text=The%20flashing%20yellow%20light%20means,Who%20It's%20For
Yellow/mod becomes Caution and orange/con becomes Serious … let’s lobby for it!
I really agree with a lot of the analysis in this post but disagree with the takeaway!
Moderate can mean either “small avalanches in specific areas OR large avalanches in isolated areas.” I think the term “scary moderate” does a really good job telling you which situation you’re in. Is it a widespread but shallow windslab problem? That’s regular moderate: be looking for windloaded slopes, use all your slab-detection skills when you encounter one, and maybe you can avoid the problem. Crucially, if you avoid terrain traps, the consequences might not be so bad if you mess up the terrain management. And if you find a suspect slope and drop a cornice hunk on it, you can gain some actually insight into its likelihood of sliding.
But if it’s a lingering persistent slab problem, “large avalanches in isolated areas,” that’s classic “scary moderate” Your approach might be totally different. The regular clues (shooting cracks, whoomphing) might not be present. The consequences of being on the wrong slope could be dire. I would generally be much more likely to close whole aspects and elevations to travel. “just going and having a look” might not be useful because of the lack of clues. Testing is less useful due to persistent slab being so weird and location-driven.
i think the term really does a good job shorthanding the different mindsets between widespread, potentially manageable problem and a localized, very high consequence problem. Just using a term doesn’t prevent further discussion of the whole advisory, but it allows one to do so with more precision If people don’t understand, i think the solution is to educate them. I always try to make sure everyone on the team is on the same page.
I’m with you — make sure everybody is on the same page!
Simplified scale hereby proposed, for likelihood of an avalanche big enough to kill a person :
Green= “Unlikely”
Yellow= “Possible”
Red = “Likely”
.
I like this scale, and let’s be honest, there would probably be the same amount of fatalities, if not fewer.
Problem with this approach is that it further short-hands the discussion … leaving out the potential for adjusting the rating for distribution … “Possible” in a very narrow band of the rose/altitude is still possible, albeit isolated … it’s a tricky medium the forecasters are working in!
Hi, Rob,
Thanks for taking time to share your thoughts on this. I have to agree with your commenter N. Kane above; I find “scary moderate” to be a really useful term for getting my avalanche students to recognize that there are nuances within the single word hazard rating, which should then lead them to discuss each avalanche problem and its location by aspect and elevation. I think novice backcountry travelers might make a decision based only on the one word hazard rating, but a good Level 1 should teach students to understand the avalanche problems and how they can use terrain to avoid them. The inherent unpredictability of persistent problems, and the lack of red flags (as Nathaniel pointed out, the cracking, collapsing/ whoomphing) that remind us of their presence, explain in part why persistent slab and deep persistent slab are the problems associated with almost 70% of fatalities in avalanche accidents over a 55 yr span in Drew Hardesty’s essay, “Expert Intuition and the Avalanche Problem.” I think “scary moderate” can heighten awareness that not all moderates are alike, and cause the forecast reader to dig deeper. I liked being forced to examine why I use the term, so thanks!
Cheers!
Jenna
Rob you may not be an influencer (yet), but that mountain athlete deal with whoop has got to be coming soon right?
Was just discussing this with a ski partner about our local forecast, noticing that in earlier yrs Considerable was used far more extensively. As our forecast region has gotten a bit data richer, and perhaps as forecasting and forecasters has changed/evolved, there is far more Moderate. And, you know need to really read and think carefully about moderate and how it specifically relates to your trip location and avalanche problem and size. Before we’d think about is this real Considerable or Considerable/Moderate. Now we’re looking at the moderate saying, hmmm the recent conditions seem like they warrant real attention, why exactly are they calling it Moderate and not Considerable?
For the record the Sierra has had scary moderate conditions a couple times just in the last few years though admittedly it doesn’t last as long as it does further inland. 🙂
Pretty much any forecast has a summary section that just gives the danger rating for each elevation and frequently when a forecast is imported somewhere else like the map on A3’s homepage the entire forecast is reduced down to a single danger rating. The problem with this is that the danger rating doesn’t do a good job of summarizing what most people think of as avalanche danger.
My experience with the term has been people using it to emphasize that you should really dig into the forecast details, more so than with a normal Moderate rating.
I think your argument is that everyone should always fully dig in on all the forecast details, which is obviously the best option, but human nature being what it is I’m not sure that’s realistic. And if that is really the goal then why not remove danger rating entirely, and just rely on the specific problems?
In my opinion a better option would be to use a different summary device that better communicated the mix of likelihood, consequence, and avoidability that seems to form the mental model of level of avalanche danger that most people have.
So basically what I’m saying is please write a post or two debating the nuance and merits of the scale itself. 🙂
Great article. I think the general complaint and summary of all the comments is that we mix interfaces. The current system is great for describing regional-scale avalanche probability for many applications, also for mountain folk. such as highway operators. It is an assessment scale. It’s application requires significant skill.
There may be room for an application scale for snowsports users. There are some interesting proposals such as a traffic light proposal. I would personalize it.
I would have a recognizable mascot. Please allow for an example for a weak layer moderate situation.
Ullr says:
– Info: Venturing on to slopes steeper than 30° may seem justifiable, but could be deadly, especially on shadowed slopes where deep persistent snowpack instability is common.
– Safe bet: It is more fun to ski without the realistic dread of catastrophe. Stick to slopes considerably less than 30°, also the slopes that you do not ski on and are above and below you.
– Risky bet: Should you venture out into steeper slopes, sunnier aspects should be less prone to large, catastrophically destructive avalanches. Beware!