Persistent Weak Layers and forecasting.

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Originally Posted by tgapp

i think - the biggest difference is - long time tourers are able to pick up on more contextual data, have a longer history with the place (they remember that big year back in 2001), and spend less energy making decisions.

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Thinkin out loud here, w/r/t the deep slab problem and forecast communication...

Imagery of deep slap avalanches is powerful (eg, Gunderson's shots of Baker sidecountry with 10 ft crowns, chairlift in view).

Would it be useful to add slope-specific avalanche imagery to the forecast page as historical context when deep slab problems are in play? Perhaps it could help folks understand the risk they may be taking on when touching certain terrain.

"In 2013 during a similar pattern, deep slab avalanches occurred on the NE faces of Cock's Knob, Pube Glade, and Choad Hollow. Click the pin on the map to explore more past avalanches in this area."

Maybe not as useful for the olde guarde, but some folks gloss over the discussion and could be better informed of the potential with embedded historical imagery.

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In 2013 during a similar pattern, deep slab avalanches occurred on the NE faces of Cock's Knob, Pube Glade, and Choad Hollow. Click the pin on the map to explore more past avalanches in this area.

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I'm not finding these slopes on GAIA or CalTopo, could you please drop a pin?

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Originally Posted by Norseman

Thinkin out loud here, w/r/t the deep slab problem and forecast communication...

Imagery of deep slap avalanches is powerful (eg, Gunderson's shots of Baker sidecountry with 10 ft crowns, chairlift in view).

Would it be useful to add slope-specific avalanche imagery to the forecast page as historical context when deep slab problems are in play? Perhaps it could help folks understand the risk they may be taking on when touching certain terrain.

"In 2013 during a similar pattern, deep slab avalanches occurred on the NE faces of Cock's Knob, Pube Glade, and Choad Hollow. Click the pin on the map to explore more past avalanches in this area."

Maybe not as useful for the olde guarde, but some folks gloss over the discussion and could be better informed of the potential with embedded historical imagery.

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Considering that many avalanche paths behave similarly year after year I think that is an excellent tool. No idea where the funding would come from though.

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Originally Posted by Foggy_Goggles

I'll watch that video tonight maybe. Just spitballing, but maybe there is some frustration it trying to the thirst for progression with "there is no substitute for experience"?

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I think that's part of it, yeah, but I also mourn the loss of mentoring culture in the mountains. I'm (intellectually) just fine with the fact that it'll be another 20 years before I am experienced, and I don't feel any angst towards that notion - there's no shortcut to time spent in the mountains. The challenge I face is navigating the next 20 years safely.

I started climbed seriously ~16 years ago, just as mentoring died out as a community practice (I think we can thank the internet/social media for that one). The first person to take me ice climbing was Scott Adamson (RIP), and I feel lucky to have gotten to climb and be mentored by the old guard in Idaho (Reid Dowdle, among others). Unfortunately, I think that era of mentoring as a means to access the mountains is now largely over, and I'm left, with my friends, looking at Caltopo, plotting tours, obsessing over UAC information doing all of those things as best as we can...and still making big mistakes along the way.

In the ski community I feel a tension between the old guard and the new; complaints about social media, a lack of knowledge around skin track or safe travel etiquette, and places having more and more recreationalists all contribute to that dynamic. Relatively two dimensional caricatures of newer backcountry skiers add to the perception that we're just a buncha park rats (nothing wrong with that) with no regard to safety. And - I'm not saying that such a dynamic doesn't exist ("Bruh I just got a sweet touring set up, wanna go ski in the BACKCOUNTRY??") - but the number of young, semi-experienced recreationalists who are dying out there just breaks my heart - that is MY demographic, and while there is no excuse for experience, those with experience sometimes seem to be quick to criticize but slow to constructively contribute. Not saying it's their fault either - if I were them, I'd be salty too. We're a buncha shitheads 90% of the time.

So, all I'm saying is this - if you come across newer/younger skiers who are doing dumb shit (putting the skinner in wrong, skiing between false islands of safety, communicating poorly, dropping in above other skiers, whatever), kindly say something. If you really want to go the extra mile, offer mentorship or a day of touring - I know that I'm not alone in saying that I would GLADLY pay for a day out in the mountains with one of my elders - buy gas, beer, carry the lunch up, a nice bottle of whisky, whatever.

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Originally Posted by Norseman

Thinkin out loud here, w/r/t the deep slab problem and forecast communication...

Imagery of deep slap avalanches is powerful (eg, Gunderson's shots of Baker sidecountry with 10 ft crowns, chairlift in view).

Would it be useful to add slope-specific avalanche imagery to the forecast page as historical context when deep slab problems are in play? Perhaps it could help folks understand the risk they may be taking on when touching certain terrain.

"In 2013 during a similar pattern, deep slab avalanches occurred on the NE faces of Cock's Knob, Pube Glade, and Choad Hollow. Click the pin on the map to explore more past avalanches in this area."

Maybe not as useful for the olde guarde, but some folks gloss over the discussion and could be better informed of the potential with embedded historical imagery.

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THIS. this is the type of communication strategy that i think could be effective.

the problem is, IMO, if you say "we had this sort of problem in '92, where Smalldick Trees ripped big", there is some chance that skiers will read between the lines and infer that a slope NOT mentioned or visualized is somehow safe. that can be addressed with effective messaging to accompany that representation, but words are rarely as powerful as images.

data viz and communication strategies are being used all over the commercial world, and i see this progression as logical and helpful in getting recreationalists of all experience levels to internalize the forecast and own their decision making. reading about a considerable avy danger is an emotionally different experience than seeing a 10' crown, or an excavation site from a fatality with a backpack at the bottom of it.

My demographic is dying too. I've volunteered to help with fields days for an an avalanche awareness org for decades but I don't generally go ski touring where there are other people around. That's my risk factor, I hate tracks and I hate backcountry shit shows. I frequently manage this by not going which sucks but it effective. I usually relax in the spring.

There is some trend to demographically generalize friction....old/young, new/experienced, skier/snowboarder etc...etc..it's bullshit and as old as the day is long. The backcountry is busy, but hey, we are the crowds.

People always talk about mentorship but they don't really know what it means. Too many potential mentees come off like absolute hard-ons that want to be spoonfed information that doesn't exist and are not willing to admit there shortcomings. Too many potential mentors are know it alls who are looking for a confidence boost from having a bunch of grovelling sidekicks.

Make friends, ask questions.

IMO we overcomplicate the PWL problem, and we do so because we're looking for a solution that doesn't exist. I do not think more information is the answer. It is a common affliction with all informed and motivated b/c users (but moreso with newer ones IMO) to scour the earth for the key piece of information that will allow them to rationalize/nuance/thread their way into "grey area" terrain. There is no grey area during a PWL instability - you're either in/under avalanche terrain or you're not, and if you're in it, you are rolling the dice. I'm beginning to latch onto the idea that teaching PWL alongside more manageable problems like windslab, storm slab etc. confuses the issue.

The difference with wily vets IMO is not some ninja knowledge about the micro feature over there that ripped in 1992, it's simply that they have recognized that there is no outfoxing this problem, and have finally accepted that they can only "win" by avoiding it. At that point it becomes a game of identifying avalanche terrain (pretty easy) and avoiding it (the hard part).

It's really simple in theory - do not fuck with avalanche terrain during a PWL instability. In practice, it is much harder to apply. I took higher level classes because I thought it would unlock more terrain, and it took 10+ years and L2 education to fully understand that there are no keys to the steep/deep castle during PWL. If I'm being 100% honest, I'm not there yet as I will catch myself trying to game my way into something on the margin occasionally.

What North said way better than I did

Unlock terrain = up up down down A button B button

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Originally Posted by Norseman

Thinkin out loud here, w/r/t the deep slab problem and forecast communication...

Imagery of deep slap avalanches is powerful (eg, Gunderson's shots of Baker sidecountry with 10 ft crowns, chairlift in view).

Would it be useful to add slope-specific avalanche imagery to the forecast page as historical context when deep slab problems are in play? Perhaps it could help folks understand the risk they may be taking on when touching certain terrain.

"In 2013 during a similar pattern, deep slab avalanches occurred on the NE faces of Cock's Knob, Pube Glade, and Choad Hollow. Click the pin on the map to explore more past avalanches in this area."

Maybe not as useful for the olde guarde, but some folks gloss over the discussion and could be better informed of the potential with embedded historical imagery.

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Don't most forecasts already do this only with current conditions and recent avalanches? Right now, on the CAIC homepage there is a picture of a 15' crown, that's pretty dramatic. I'm sure with unlimited resources and funding avalanche centers would love to create all these cool tools and databases but that is not their reality. And they won't make much of a difference, people will still find ways to get killed.

I backcountry skied for about 15 years in continental snowpacks without many issues or incidents. Then in the last 5 years I've lost one friend, an acquaintance, and almost had 2 partners killed. PWLs played a role in the incidents with my partners. They were on the same 31 degree slope one year apart, already skied a dozen times, and when it slid the first time the old timers never recalled it going that big. These experiences really hit me hard, I realized I had been getting away with it for 15 years and the whole time I thought I was being safe. I now ski mostly inbounds mid-winter and wait for the spring to tour, my new touring skis haven't seen snow this year. So people who are new or semi-experienced, use this season as a year to learn, because in 20 years you'll be the old-timer who recalled that meadow going big in 2021.

Huge avalanche in la grave this morning.

Sent from my Redmi Note 8 Pro using Tapatalk

Probably repeating others here, but I'm also of the "no avy terrain" approach through winter, and then starting to raise up my head come "spring" - although obviously no magical date. I still follow the advisories on a daily basis through the winter and like to dig around in the snow, but in the end just maniacally keep checking slope angles (caltopo overlay + inclinometer) around me and especially above, with goals of 1) never touching 30, 2) avoiding convexities and 3) staying out of traps. Kinda "duh", but I think it does take a maniacal focus to avoid wandering into danger.
Oh, and I miss the old telemarktips avy eyes posts/pics!

Yeah I'm not sure I'm all for the idea so don't chew me too hard for putting it out there.

I see it more as a way to help people realize what is and is not true avalanche terrain.

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Originally Posted by tgapp

THIS. this is the type of communication strategy that i think could be effective.

the problem is, IMO, if you say "we had this sort of problem in '92, where Smalldick Trees ripped big", there is some chance that skiers will read between the lines and infer that a slope NOT mentioned or visualized is somehow safe. that can be addressed with effective messaging to accompany that representation, but words are rarely as powerful as images.

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One solution might be to not name slope itself, rather describe slope angle, aspect, features, etc in an effort to relate such events to a set of conditions rather than a specific location.

Norse, I volunteer at NWAC and a few years ago, I suggested that the forecasts in their assessment add in the specific location of their findings. The assessments would consistently would say: "NW facing slopes" or some vague thing, when I could often pick out their exact location in the picture. Now they often say the specific location, then mention to be aware of similar facing/elevation. They're getting better at this, but I think your idea is spot on. Why not add in historical info?
We're at a tipping point right now, (dramatic increase in BC users), and frankly I just want to see less dead people.

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Originally Posted by tgapp

THIS. this is the type of communication strategy that i think could be effective.

the problem is, IMO, if you say "we had this sort of problem in '92, where Smalldick Trees ripped big", there is some chance that skiers will read between the lines and infer that a slope NOT mentioned or visualized is somehow safe. that can be addressed with effective messaging to accompany that representation, but words are rarely as powerful as images.

data viz and communication strategies are being used all over the commercial world, and i see this progression as logical and helpful in getting recreationalists of all experience levels to internalize the forecast and own their decision making. reading about a considerable avy danger is an emotionally different experience than seeing a 10' crown, or an excavation site from a fatality with a backpack at the bottom of it.

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UAC started doing this about a week ago, not sure if it was before/after the 6th. But this is the bottom of today's PWL section:


"Particularly dangerous areas would include Snake Creek, upper American Fork, upper Mill Creek, and much of the Park City ridgeline."


I agree, for touring parties that (unfortunately or whatever) don't have all the information descriptions like this up front are helpful to create "no go" zones. It seems like most in this thread would agree that any and all aspects/elevations with a PWL are no go, but for someone that may not know that, or understand the issue fully, I think what UAC is doing is going to prove helpful.

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Originally Posted by tgapp

So, all I'm saying is this - if you come across newer/younger skiers who are doing dumb shit (putting the skinner in wrong, skiing between false islands of safety, communicating poorly, dropping in above other skiers, whatever), kindly say something. If you really want to go the extra mile, offer mentorship or a day of touring.

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I talk to people about this sort of thing regularly. Most are very receptive. Every so often someone seems to think I'm mansplaining. I'm ok with that.

There are a couple strategies I use to get people to listen and not think I'm a know it all:

1) Ask questions, such as, "I wonder if skinning up that way could expose you to danger from above?" This lets someone come up with their own solution to a problem they're about to cause, rather than just telling them they're wrong. As a former classroom teacher I've used this approach thousands of times and it works in any context.

2) Offer some positive information about where to ski along along with a warning about places to avoid: "The top is usually wind scoured, but there is a slight depression below that rock that is just sheltered enough to have softer snow most of the time (positive). But when you reach those two trees there is a rollover that slides naturally every couple years (warning). It's small but it can drag you into the dense trees underneath (consequences). So I avoid that spot even when the snow is pretty stable. There are good, safe turns to left anyway and it's usually deep there (positive)." People are usually psyched for this kind of info (I would be) and tend to listen carefully. But if I say, "watch out for the rollover" I give less incentive for them to pay attention and increase the chance that I'm dismissed as a crotchety grey beard.

I don't want to oversell my experience of expertise (there are many posting in this thread with more of both) but if anyone on the Front Range wants to going skiing and talk about terrain management and not dying in an avalanche you can PM me.

Remember guys, your situation in Wasangeles is a bit different from everywhere else. You have so much historical data and so many users that you may be able to use data to do some type of smart guy probability mapping. That doesn't mean it is a great idea or is applicable to other areas.

Pro-tip: I don't know anyone that would use historical data about what has or has not slid within their lifetime to green light a slope during an recognized PWL problem. Despite the tone on this conversation being net positive, it seems like the "don't trust a deep slab" message that mentors and forecasters and guides and instructors have been preaching for decades in rubbing in.

You are reaching. The answer does not exist. Just because the freshie pow pow on West Whistledick hasn't slid in 30years does not mean in is not gonna slide and kill me today. We can't run a Monte Carlo Simulation to establish the probability. What we can do is ski tracked out bullshit on East Whistledick because it is 25degrees, is outside the alpha angle of other hazard, enjoy our day out in the mountains with our friends, lament about how it used to be with safe freshies everywhere, save our money for a snowmobile and wait for spring.

Why did the FUAC stop their 3-day program? I took it about 15/16 years ago and found it to be very useful and affordable. Affordable in a way that it won’t kill your budget to take it annually or every few years and useful where you’ll gain new levels of understanding each time you take it.

Something that I sometimes read in the forecast discussions but I feel many seem to miss is that some slabs that sit on and release from PWLs will pull out on slopes much less than 30*, depending on multiple circumstances. Discussion is pretty common about the potential of triggering the slab from below, but there’s also potential that the slab will pull out from an above flat ridge line and very low angle areas along the flanks.

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Something that I sometimes read in the forecast discussions but I feel many seem to miss is that some slabs that sit on and release from PWLs will pull out on slopes much less than 30*, depending on multiple circumstances. Discussion is pretty common about the potential of triggering the slab from below, but there’s also potential that the slab will pull out from an above flat ridge line and very low angle areas along the flanks.

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Got any more info that that? Are you talking about local connect terrain below 30* or a propensity of avalanches failing on PWLs to run on terrain <30*. If the later, I'm very interested as that is not part of my risk reduction paradigm.

I'm really loving that numerous other people on here are saying they avoid terrain over 30deg most of the winter, namely during a persistent layer, and wait until spring to get steeper. Makes me feel a lot better about not getting in the awesome looking, big terrain up high. The vast majority of the things I ski (split) are low 30s and less, def less than 35deg (not immune to sliding). Always feel like I'm just more scared than everyone else, but in talking to a UAC forecaster at the Gobbler's incident, he also said he's just scared of everything and really just skis lower angle stuff. I see a lot of tracks in open bowls, surrounded by steep slopes, and it just makes me feel like maybe I'm too conservative and missing out. Even just going up the bigger drainages in the Cottonwoods provide plenty of exposure (just look at Mineral Fork, where a slide went all the way to the drainage bottom).

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Originally Posted by bodywhomper

Something that I sometimes read in the forecast discussions but I feel many seem to miss is that some slabs that sit on and release from PWLs will pull out on slopes much less than 30*, depending on multiple circumstances.

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Originally Posted by Foggy_Goggles

Got any more info that that? Are you talking about local connect terrain below 30* or a propensity of avalanches failing on PWLs to run on terrain <30*. If the later, I'm very interested as that is not part of my risk reduction paradigm.

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If you're dealing with buried surface hoar, it's probably a good idea to be extra conservative on slope angle. Otherwise I have the same questions as Foggy.

First off, I think it is inevitable that people will continue to get into trouble. The traps are too enticing. But I like the idea of saying "deep persistent slabs" rather than "persistent weak layer". I don't really like the pinpointing of "zone X is more likely to have problems" in the forecast, because then people will go to zone Y and think they will be fine.

In the PNW and many other areas like parts of BC, people regularly and safely ski steep terrain in Winter. Which makes a deep persistent problem like what we've got all that more dangerous. Folks aren't used to the extreme caution that it requires.

Maybe this is too dramatic, but as a thought exercise what about replacing the danger rating forecast model with an avalanche problem based model (i.e. the bullet point forecast take-away is the avalanche problem rather than the danger rating)? My suspicion is more experienced users are already basing their travel on the AP anyway, rather than on the hazard rating. In a way, problems are easier for everyone to conceptualize than the likelihood / distribution hazard rating matrix. Given the increasing number of educated backcountry users (my feel is the overall level of education is increasing) this is a potential way to especially address PWL issues.

Obviously some other issues with this approach, but it's been in the back of my mind for a few seasons now.

Great discussion in here.

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Originally Posted by ryan14410

I'm really loving that numerous other people on here are saying they avoid terrain over 30deg most of the winter, namely during a persistent layer, and wait until spring to get steeper. Makes me feel a lot better about not getting in the awesome looking, big terrain up high. The vast majority of the things I ski (split) are low 30s and less, def less than 35deg (not immune to sliding). Always feel like I'm just more scared than everyone else, but in talking to a UAC forecaster at the Gobbler's incident, he also said he's just scared of everything and really just skis lower angle stuff. I see a lot of tracks in open bowls, surrounded by steep slopes, and it just makes me feel like maybe I'm too conservative and missing out. Even just going up the bigger drainages in the Cottonwoods provide plenty of exposure (just look at Mineral Fork, where a slide went all the way to the drainage bottom).

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Nah man, in a year like this, there just isn't a good way to get on steeper terrain till the spring.

^^^
Sure there is

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