Is it really PDS?

Jeff Duda

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Caught this in real-time: there is currently a PDS tornado warning for a location in W TX that is described as being "rural" (the warning text includes no place names to warn).

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The LSR says it is a law-enforcement confirmation, which already leads me to think the threat may be a bit over-emphasized. The NWS Tornado Warning feed for this says 58 people live in the polygon:
This leads me to ponder a philosophical question, even though the underpinnings are more political: is this truly a "particularly dangerous scenario" that the impacts based warnings paradigm that the NWS instituted several years ago was meant to cover? I would argue that it isn't. But then again, I suppose there is a flowchart somewhere that includes a chain ending in "if law enforcement confirms a tornado and there is a velocity couplet, then it must be PDS warned." Maybe not.

What do the rest of you think?

Also, yes, I'm aware that the PDS designation was removed a few minutes after it was warned. Maybe this was just a mis-click after all. But this is not the only time I've seen a PDS tag on a warning that I wouldn't have judged as PDS. Perhaps we could start a list of such examples here for statistical examination!
 
All tornado warnings are "emergencies." There should be one type of tornado warning. The particulars can be described in the text.

While on the topic, all of the safety junk should be gotten rid of. Did you know that some tornado warnings have more word than all four stanzas of the Star Spangled Banner? Ever try to listen to NOAA weather radio with 3 tornado warnings simultaneously in effect for that station's listening area -- I once timed it and it took 6 minutes for the content to cycle.

NWS should cut the tornado warning text and send out safety rules once the thunderstorms start to develop in the watch.
 
I am sure I read on the discord that this was a mis-click and nothing more.

It certainly doesn't help, however, that there are NWS warnings and levels, then local news stations and the Weather channel have their own designations too. For the non-weather person it's probably confusing.
 
It's something that has always bothered me about how the TORE is handed out these days. While I believe it was originally intended to be used when a large tornado is approaching a large city, it's been expanded to cover basically any town with a post office. Now, that's not a knock on small towns on my part; I grew up on a farm and have lived large chunks of my life in towns of less than 10k people. In some instances, not even within the limits of a town or city, and if I have my way, I'll have a farm of my own someday. But I feel as if it has been diluted by how freely they're issued now in terms of impacted population.

The other thing that has bothered me about the application of the TORE is how wide that polygon is in many cases. While I get trying to account for deviant motion, I've noticed some that are ridiculously wide. The best application (in my opinion) that I've seen of the TORE is the Paducah, KY office during the Mayfield event. They used the TORE like a surgeon's scalpel, and used a PDS warning to cover the areas in between cities, in stark contrast to some offices that seem to use it more like a sawzall. It's also hard for me to fathom why a person wouldn't move to cover for a tornado warning or a PDS warning, but would only for a TORE. In this instance, I think I agree with Mike in that it's gotten needlessly complicated, and as Jamie pointed out, possibly difficult for the average non weather person to understand.
 
What I hate about the PDS and TORE declarations is that they imply that we can tell in advance which tornadoes are NOT an emergency. So if there's no tornado emergency, why take cover? That's unfortunately how a significant percentage of the public will view these things.

I agree with Mike Smith: ANY tornado is an emergency! That wimpy looking rope may just turn out to be the evil twin of the Jarrell, TX F5. Who wants to discover that the hard way?
 
I can certainly see the "misclick" defense for the first case I cited, but we're seeing it again, also in a TX WFO.

population of 262 in the warning. Maybe that is enough for PDS designation. IDK. But it seems incongruous.
 

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I guess I was wrong with my original understanding of PDS...

Yes, nearly all tornadoes are dangerous, but seems like when I was looking around & trying to do some reading/learning more about storms/tornadoes/etc that "PDS" was a term they used sparingly...so I was under the original impression that as the name implies it was something kept for when a tornado was *particularly* dangerous - a level above simply dangerous.

But I see PDS in tornado warnings all the time now - seems like nearly every time there is a round of storms you can find 1 or more.

Granted its been a number of years since I was doing that (and some of it wasn't exactly new material even at that time).
 
All tornado warnings are "emergencies." There should be one type of tornado warning. The particulars can be described in the text.

While on the topic, all of the safety junk should be gotten rid of. Did you know that some tornado warnings have more word than all four stanzas of the Star Spangled Banner? Ever try to listen to NOAA weather radio with 3 tornado warnings simultaneously in effect for that station's listening area -- I once timed it and it took 6 minutes for the content to cycle.

NWS should cut the tornado warning text and send out safety rules once the thunderstorms start to develop in the watch.
I must disagree. Warning saves lives. PDS gets people to take the warning seriously! The issue is all of the amateur chasers that clog up the highways and escape routes. That is the real threat! The area of most concern is the Derecho. Hundreds of miles wide, with embedded QLCS Tornado cells. The damages is so wide spread! It would be a disaster to not warn people using attention grabbing declarations that a multi-state threat exits! A few over reactions are far better than inadequate warnings!
 
I must disagree. Warning saves lives. PDS gets people to take the warning seriously! The issue is all of the amateur chasers that clog up the highways and escape routes. That is the real threat! The area of most concern is the Derecho. Hundreds of miles wide, with embedded QLCS Tornado cells. The damages is so wide spread! It would be a disaster to not warn people using attention grabbing declarations that a multi-state threat exits! A few over reactions are far better than inadequate warnings!
Yes, warnings do save lives, but there is a flip side to this, and it is delicate balance. And it is very clear that it is a complex social/messaging issue with no easy answer for all. This has been discussed many times at all levels, but I will state it again here.

First, this -- TOREs are issued more often it appears in recent years, same with PDS warnings. Some of this is likely due to just a cycle of more active/less active severe seasons/years in the U.S. (anecdotal - only a few/several years sample size is not enough for trend facts), and some are likely due to changes in standards/practices in issuing what type of warnings and when, which is normal b/c our standards/practices are always changing and/or being fine-tuned/tweaked.

But here is the flip side, too many TOREs or PDSs will eventually cause some apathy in the public mindset. The notion is, "oh, it is *only* a 'regular' tornado warning, or not a 'particularly dangerous situation.' " This is a real problem and is fundamental to the human psyche as to how people react ('cry wolf'). So you can't just say summarily, "more warnings" or "more strongly-wording warnings" are better net-net. More is not always better. The false alarm rate (FAR) will take its toll on the public mindset. We have proof of this. Disaster survey reports post-events have found that apathy is a factor, such as with the Joplin MO EF5 in May 2011. Some people interviewed post-storm said, "we get tornado warnings all the time, and nothing happens." This is really nothing new.

As meteorologists and storm enthusiasts, *we* know better and are educated so we can recognize well often in the field or monitoring radar a more serious tornado situation or not, and take action, but you can't assume that for the general public.

But I get it, our technology does not currently allow us to fine-tune tornado warnings to that degree where we can significantly reduce FAR. How many times have we seen supercells do unexpected things in mere minutes, with no indications of tornadogenesis imminent prior. Or several supercells all rotating strongly not far from each other in the same environment, and trying to figure out which one or ones will produce a tornado soon (if at all) or if tornadoes occur, will they be short-lived and weak or long-tracked and violent?

I guess the notion "better safe than sorry" works best (e.g. issue a warning), relatively speaking, but we can’t ignore the very real consequences of over-warning and the public apathy that results.

I will add though, the large picture, as to how weather in general has been treated in recent decades with so much hype and exaggeration, is not helping the situation. Events not nearly as serious as a real-time tornado situation often are treated as "the worst ever," "unprecedented," and "extreme." For instance, yes, a snowstorm is impactful and causes disruption, but most are very manageable and not something that is going to require absolute measures in terms of impact. Or a typical hot or cold outbreak in a given region. When did we suddenly become so vulnerable to hot wx in the summer and cold wx in the winter? Like we can't handle temps 90-95 F when the average temp across nearly 50% of the Lower 48 has average high of 90 F or higher in the middle of summer? There is all too often a lack of context and perspective. And some of the public has grown tired of this endless hype and are tuning-out weather alerts and warnings completely. Again, not something we can just ignore!
 
I must disagree. Warning saves lives. PDS gets people to take the warning seriously! The issue is all of the amateur chasers that clog up the highways and escape routes. That is the real threat! The area of most concern is the Derecho. Hundreds of miles wide, with embedded QLCS Tornado cells. The damages is so wide spread! It would be a disaster to not warn people using attention grabbing declarations that a multi-state threat exits! A few over reactions are far better than inadequate warnings!
The over reactions here have caused alot of apathy in this region. A couple moderate risk days, pds tornado watches, svr storm warnings, etc. Then you don't get enough wind to knock over a lawn chair or enough rain to wet the sidewalk. A family member told me they "aren't believing shit until it's knocking on the front door". Fatigue is real amongst the general populace, especially in the heartland that deal with svr weather regularly.
 
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Add to what Boris and Matt have said: it takes a psychological toll on people to have to go into "emergency" mode too often. We aren't designed to be in a near-constant state of fight-or-flight. No one is in 'near-constant' warning mode for weather, but the point is that there is a threshold above which is "too much" for being told something along the lines of "run to the basement or die." Not every harmful situation is a true emergency and thus not every potentially harmful situation needs to be treated as one. The SBW paradigm that NWS rolled out a few years ago may have been an attempt to address the graduation of severity of needed reaction.

My as-yet-unspoken allegation in this thread is that some NWS WFOs may have decided to start using PDS Tornado Warnings a little too liberally under the impression that there is a simple linear relationship between intensity of wording and response that will hold for a given population over many years. The conclusion is that "if I issue PDS TW over a 'regular' TW, I'm going to get more response, which is what I - the warning meteorologist - wants." However, I strongly suspect that this attitude will break any seemingly linear relationship between intensity of warning wording and response urgency (if that relationship even still exists).

Once every tornado warning becomes a PDS tornado warning, then PDS tornado warnings cease to carry the weight they once did. Next you'll start seeing increases in Tornado "Emergencies". It nudges up against the notion of the "Red Queen's Race" problem.
 
Jeff Duda wrote:
"it takes a psychological toll on people to have to go into "emergency" mode too often. We aren't designed to be in a near-constant state of fight-or-flight. No one is in 'near-constant' warning mode for weather, but the point is that there is a threshold above which is "too much" for being told something along the lines of "run to the basement or die." Not every harmful situation is a true emergency and thus not every potentially harmful situation needs to be treated as one."

This sums it up better than any other way I have yet seen this issue stated! We are indeed not designed to be in a near-constant state of flight-or-flight, but ever watch or read so much the news these days when it comes to wx? It's like 'atmospheric Armageddon" is permanently upon us, and the end is nigh. That's simply not reality! And this constant state of excessive alert puts a profound stress on many, which is not healthy for the population, to say the least.

I am for one so tired of the "ordinary" getting turned into the "extraordinary." Not every tornado outbreak will be a 1974 or 2011 Superoutbreak. Not every tornado will be a Bridge Creek/Moore or Greensburg. In fact, these are extreme outliers that are the exception, not the rule. We can't be held 'hostage' by what "might" happen for every event forecast, and can't treat every event when it's over as 'catastrophic.' Going full throttle all the time dilutes things so people have no idea how to distinguish between something that is run-of-the-mill from something truly historic/excetpional. And don't get me wrong, all wx events are dangerous at some level and in some form, but it is important how we treat and react to them.
 
The PDS/tornado emergency watch/warning track record has been abysmal post-Greensburg. I am surprised those aren't just nixed altogether by the higher-ups (go back to just straight tornado watches and warnings). Our science/capabilities that would allow for those types of distinctions clearly isn't there yet.
 
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