What is "a developing tornado"

[rdale]

Pulled this out of the DISC thread since it wasn't specific to yesterday...

Matthew reposted info on "spotters indicating a developing tornado" in the NOW thread, and I'm curious what that means. In my mind, either it IS a tornado or it IS NOT a tornado. So what is a "developing" tornado? Since we don't know that every funnel is going to reach the ground, how do you know what cloud feature is going to develop into a tornado and what cloud feature will not?

Is it just a funnel cloud half-way down? A rotating wall cloud? Rotation in the mid-levels?

- Rob

[Josh Murfield]

I would guess when someone mentions a developing tornado they do mean a funnel. If you've been watching a wall cloud and then see a funnel starting to pull down from it, that to me is one of the later stages of tornado development (or birth, whatever you want to call it :) , even though it may never actually touch the ground becoming an actual tornado.

[Brian Emfinger]

I agree that doenst make a lot of sense to say "reporting a developing tornado". Its either a tornado or its not. They must know more than I to be able to say a tornado is certainly developing from a particular storm. We all see lots of wall clouds and storms that we would consider supportive of tornadic intensity that dont produce (several yesterday) so how would you know when its going to produce or not? And of course the opposite is true as you can have tornadoes form from storms that looking at you wouldnt think would produce a tornado.

[Brian Stertz]

I would have to say that an experienced chaser truly can tell when a tornado is imminent. Likely by the time the report of a developing tornado is called in, the tornado is on the ground already. So time sequence wise it would be wise to call in the report as a tornado or at very least a funnel cloud for the warning purposes.

[Skip Talbot]

This was part of a NWS issued warning wasn't it? Let's remember the target audience of warnings: the general public. So if several spotters are reporting increasingly organizing wall clouds, some with rotation, and/or funnels, it makes sense to relay to the public that a tornado may be (or is) developing. Not too many ordinary people actually know what a wall cloud is, so reporting one over the weather radio might be meaningless. The job here is to get the word out that a tornado may be imminent, not to be scientifically accurate.

[rdale]

I don't agree with your statement. The target audience of the TEXT of the warnings though is TV mets & EM to pass that info on to the public... VERY few Joe Publics get that part of the warning. So if the TV guy knows there's a rapidly rotating wall cloud, he can emphasize that. If this "developing tornado" is just some mid-level rotation, I'm not going to push nearly as hard.

I see many offices also say "spotters report a severe thunderstorm" without saying what happened... Was it 3" hail or a 90mph gust? I think those differences need to be indicated too.

So time sequence wise it would be wise to call in the report as a tornado or at very least a funnel cloud for the warning purposes.

I _strongly_ disagree with that... If there is nothing happening on the ground, do NOT call it in as a tornado just because you are worried about communication delays.

[rdale]

...and the kicker is that (at least per preliminary reports) there was no tornado to come from this storm... A separate cell in the county has a law enforcement report of a touchdown but no damage.

[Robert Dewey]

I don't see a problem. I can understand that "developing tornado" is probably similar to "a tornado is imminent" - however, I do agree that it would be more beneficial if the NWS would put spotter reports in (or at least narrow down the expected event type). When I see a bow echo blasting east and see "severe thunderstorms can produce large hail and damaging wind", I really think the wind aspect should be played up a bit more (i.e. expect winds up to 70MPH, or "spotters reported 80MPH in PickAName Township"). Spotter reports make an SVR or TOR more credible IMO.

[Willie Dines]

I think that the referrence of "A Developing Tornado", might actually be a funnel cloud that is barely touching down, e.g. only beginning to whip up dirt or debris, but the funnel still not completely on the ground.

I do agree though, that a report should be either a funnel cloud or tornado, it's best to keep things simple, especially when it comes to giving out warnings, the simpler and straight forward the warning, the less time taken to give the warning and more time for people to get to their basements, storm cellars, etc :)

Willie

[Andrew Herron]

If there is a funnel and there is a debris cloud, by NWS definition, that is a tornado.

No debris cloud, no tornado, that simple.

I think that the referrence of "A Developing Tornado", might actually be a funnel cloud that is barely touching down, e.g. only beginning to whip up dirt or debris, but the funnel still not completely on the ground.

[Willie Dines]

If there is a funnel and there is a debris cloud, by NWS definition, that is a tornado.

No debris cloud, no tornado, that simple.

I know that, but if a spotter is calling it in as a developing tornado, then they might be typing up the information being passed on by from the spotter, but I agree with you wholeheartedly, and I previously mentioned that it should either be called in as a Funnel Cloud or Tornado :)

Willie

[rdale]

If a spotter said "developing tornado" to anyone with weather knowledge he would immediately be asked to clarify... The same response you'd get if you said "winds are strong"

[Terry Tyler]

i think its more of a conflicting terminology issue...whether or not it is on the ground...i would say a "developing tornado" is just as the name implies...a developing tornado...

it might not make it to the ground or anything, but its beginning to form and if it continues to develop, then it will become a full-blown tornado...i guess you could call any funnel cloud a "developing tornado" but then again...its not a tornado yet so...

IMO, a developing tornado is a "developing" tornado...all kinds of things develop, but not always come out to be what they were gonna be...

the same can be said for tornadoes...

[beaudodson]

I don't agree with your statement. The target audience of the TEXT of the warnings though is TV mets & EM to pass that info on to the public... VERY few Joe Publics get that part of the warning. So if the TV guy knows there's a rapidly rotating wall cloud, he can emphasize that. If this "developing tornado" is just some mid-level rotation, I'm not going to push nearly as hard.



Hmmm on the target audience. Actually a lot of people hear the warning on NOAA Weather Radio or directly through the Radio-EOS broadcast. This WOULD include the text of the "developing tornado" - I would say a huge number of people do hear the actual text. Depends on whether you are watching tv or not. Thousands will hear the warning on their weather radios or radio.

[rdale]

Even if they do get the entire warning shown or read to them, do they listen to the entire text of the warning? Do they know the difference between "doppler radar indicates" or "NWS meteorologists detect" or "developing tornado"? If you asked them 30 seconds after listening what exact phrase was used, would they remember? No way. So if you say 10% of the public gets their info this way, the rest from tornado sirens and TV, I still don't call Joe Public the primary audience of the text details.

[Mikey Gribble]

The only time I have ever used the term developing tornado was when there was extremely/extraordinary rapid rotation and vertical motion very close to the ground, to the extent that a tornado seems all but immenent. In my mind, it is a way to make a distinction between just a funnel and a situation where a tornado is extremely likely. I have only used the term once or twice though. I can't even remember if there was a funnel when I did it (it was a couple years ago), but the storm did tornado.
That was just my own personal feelings when I said it though. I have no idea why it was used in this case. I like Terry's explanation. Just because somebody says developing doesn't mean it will develop. Thought of this way it is virtually interchangeable with the typical "funnel" term used in warnings as far as content is concerned.

[Willie Dines]

If a spotter said "developing tornado" to anyone with weather knowledge he would immediately be asked to clarify... The same response you'd get if you said "winds are strong"

That's true and a good point of which, I agree wholeheartedly with also :)

Willie

[Dustin Wilcox]

Does it really matter? Rather its Tornado, developing tornado, midlevel rotation, Doppler radar indicated tornado, funnel cloud and what ever other terminology you want to add, people should be taking shelter and the NWS should be issuing a warning with just as much urgency. Thus debating the significance of the Term "developing Tornado" and its impact in warning the public is pretty insignificant IMO.

[rdale]

Dustin - apparently you missed the "Tornado Emergency" thread ;>

If the media knows you've got a tornado on the ground, we'll cover it MUCH different that if it's rotation in the cloud base. That's why we want as much detail as possible in the reports. Some offices rock at that, others -- not so good. And since (regardless of how the intial info gets out) a large majority of people get their continuous coverage from TV, it's in everyones best interest to make sure we have as much to go on as possible.

[beaudodson]

I would be curious what % of the public gets their warnings from television compared to NOAA Weather Radio, Car Radio, Sirens, TV Cable (which reads the warning), and so on. I guess we don't have any stats on that? I would guess in this region it could go either way. Majority prob from NOAA Weather Radio, Car Radio, and Cable (non local channels). I would say the minority get them from the local ABC, CBS, and NBC Station (which would be the on-air met). Twenty years ago most people would have gotten their warnings from the local on-air met (that was before cable was widespread). Now I am not so sure about that. Maybe someone has some stats.

Regardless I don't think most of the public cares one way or another. It is like saying "radar indicates a possible tornado" - or something similiar to that - not sure most people even care.

I would, however, say that 90% of the people interested in weather would know what a developing tornado means. Whether it is or is not proper wording. It is like saying "tornado on the ground" - well to be exact that is all a tornado can be - on the ground. If it isn't on the ground then it isn't a tornado.

[beaudodson]

Dustin - apparently you missed the "Tornado Emergency" thread ;>

If the media knows you've got a tornado on the ground, we'll cover it MUCH different that if it's rotation in the cloud base. That's why we want as much detail as possible in the reports. Some offices rock at that, others -- not so good. And since (regardless of how the intial info gets out) a large majority of people get their continuous coverage from TV, it's in everyones best interest to make sure we have as much to go on as possible.
Little doubt a tornado that is doing damage will get more attention around here. Wall to wall coverage. This is why it is a good idea to have specific details in warnings - updated warnings as well. The more information the better...for the public.

[rdale]

I would, however, say that 90% of the people interested in weather would know what a developing tornado means.

Given the rest of the thread I forgot that was my initial question ;> What does "developing tornado" mean? No tornado was reported, so while I might consider it a funnel cloud approaching the ground either it aborted development or it means something else to that spotter / NWS office.

[beaudodson]

On the question "what is a developing tornado" - I hear the NWS use this terminology quiet often. I always assumed that it meant there was rotation at mid-levels and now they are seeing rotation further down in the storm - so the next logical step is that there might be a developing tornado. If a spotter used these words though...that is a bit odd. heh You either have a wall cloud, rotation wall cloud, funnel cloud, or a tornado. Not sure what else you could have. If I saw a funnel cloud and it was coming down out of the clouds then I would tell the NWS that we have a funnel cloud that has almost reached the ground. They can figure the rest out for themselves.

[beaudodson]

Given the rest of the thread I forgot that was my initial question ;> What does "developing tornado" mean? No tornado was reported, so while I might consider it a funnel cloud approaching the ground either it aborted development or it means something else to that spotter / NWS office.
Yeah read above. If the NWS says this in a warning then, to me at least, it makes more sense than a SPOTTER saying that. Not sure why a spotter would use those words.

[Mikey Gribble]

First of all, I think this discussion is pretty ridiculous. What difference does it make whether the text of a tornado warning says "funnel" or "developing tornado"?

Second, not every tornado has a negligible funnel before you get circulation at the ground. Rapid vertical motion and rotation close to the ground (not just a run of the mill rotating wall cloud) should be considered just as serious as a funnel from an operational standpoint and using the term "developing tornado" conveys that when there isn't a funnel present. I have no clue why the NWS said "developing tornado", nor do I care, but that is one circumstance where I would tend to think the term "developing tornado" would be a wise choice of words. It get the publics attention more than "rotating wall cloud", which would be the other option in that hypothetical situation. IMO there is absolutely no meaningful difference between the terms developing tornado and funnel. Why is everybody being so damn picky on semantics this year? First it was vault, then mesocyclone, now we are onto warning text.

[rdale]

"What difference does it make whether the text of a tornado warning says "funnel" or "developing tornado"?"

Because info I'm getting now is that the spotter simply reported rotation in the cloud base, no funnel, no wall cloud, nothing. If I'm wondering about going wall-to-wall and the warning is just because a spotter saw some rotation in the storm, I'm going to make a much different determination than if a spotter see a funnel 50% down to the ground.

And why do people get so upset when questions are asked? Why does a discussion have to fit the mindset of a few or it's "ridiculous"? Seems like a lot of people are participating, so I guess a lot of us enjoy these chats.

[Dan Dawson]

...and the kicker is that (at least per preliminary reports) there was no tornado to come from this storm... A separate cell in the county has a law enforcement report of a touchdown but no damage.

I can confirm (as nearly as possible, at least, in the dark with only lightning for illumination) there was a tornado with this storm. The warning in question came out over the radio just as we were watching a newly-developed multiple vortex tornado in that same area SW of Lipscomb.

[Dick McGowan]

"What difference does it make whether the text of a tornado warning says "funnel" or "developing tornado"?"

Because info I'm getting now is that the spotter simply reported rotation in the cloud base, no funnel, no wall cloud, nothing.

I was watching this on GR3 with spotternetwork last night on my way home...and someone reported a "Wall cloud" I'm assuming it was rotating. I'm also going to bet that's how they translate it to "Developing tornado."

[Mikey Gribble]

Rdale, it seems like you are acting like the spotter report in the NWS text is the only thing you have to base your decision on whether or not to go "wall to wall" with coverage. You have numerous other tools at your disposure to help you decide what kind of coverage the storm deserves, so I think you are overplaying the importance of the NWS warning text as if it were the sole indicator of storm strength.
You are also jumping to the conclusion that a "developing tornado" just means "rotation in the cloud base". It could mean exactly what I said, rapid rotation and vertical motion very close to the ground, which is just as good of an indicator of a developing tornado as a funnel is. I would take the term developing tornado to mean just that, there is a tornado developing. Doesn't seem very complicated to me. I don't need an exact visual description of the updraft base to understand that.
If you are a TV met then you shouldn't have any problem calling one of the on duty meteorologists at the local NWS office and asking them what exactly the spotter saw/said if you can't figure out the storm threat for yourself. If you are basing your decision on whether or not to go "wall to wall" off a single anonamous "spotter report", then I think that is a problem in and of itself.

[Terry Tyler]

First of all, I think this discussion is pretty ridiculous. What difference does it make whether the text of a tornado warning says "funnel" or "developing tornado"?

Second, not every tornado has a negligible funnel before you get circulation at the ground. Rapid vertical motion and rotation close to the ground (not just a run of the mill rotating wall cloud) should be considered just as serious as a funnel from an operational standpoint and using the term "developing tornado" conveys that when there isn't a funnel present. I have no clue why the NWS said "developing tornado", nor do I care, but that is one circumstance where I would tend to think the term "developing tornado" would be a wise choice of words. It get the publics attention more than "rotating wall cloud", which would be the other option in that hypothetical situation. IMO there is absolutely no meaningful difference between the terms developing tornado and funnel. Why is everybody being so damn picky on semantics this year? First it was vault, then mesocyclone, now we are onto warning text.

i agree...ive seen alot of videos (like the manchester tornado) when the wall cloud motion is so violent...its only a matter of time before a tornado begins to form...

bottom line is...its really just a warning...theres no need to dwell on small idiosynchrasies as far as warning text is concerned...its a warning and thats that...theres a dangerous storm in the area, and its a tornado warning...

the general public doesnt care whether its a tornado emergency a developing tornado or whatever...its a tornado warning...hyped up terminology, and enhanced wording may give an imminent since of danger, but it is really up to the individual...warning or no warning...to heed or not to heed the warning...tornado or no tornado...ive been in a million tornado warnings and never saw a single tornado...

again...i dont see any need to criticize a warning...there were alot of tornado reports from the storm, but whether it was weak, producing or not producing...the general public needed to take shelter...there was a funnel, and putting yourself in the warning coordinators position...with the greensburg event in mind...issue a warning...if it doesnt make a tornado, then thank God...

again...it is a tornado warning...tornado or no tornado...which from a terminolgy stand point means "a tornado is either IMMINENT or occuring" within the warning area...a "developing tornado" or rotating wall cloud or funnel indicates the IMMINENT possibility of a tornado...reguardless of a tornado or not...

i personally think a warning is just that...a warning...

[rdale]

there were alot of tornado reports from the storm

Just to clarify - per the reports there were no tornadoes logged from that warning... There was an unrelated police report of a tornado with no damage on a separate cell in the county, but nothing from the warning I'm asking about.

And again it wasn't supposed to be a big deal. I asked what people think a 'developing tornado' is and consensus appears to be unreachable ;>

In my mind the NWS should report exactly what the spotter sees, but feel free to disagree.

[Jason Boggs]

I tell you what, the best instance of a "DEVELOPING TORNADO" that I have ever seen was over the town of Stinnett yesterday. In the 10 years of chasing for me, I have never seen such rapid tornadic rotation without actually producing a tornado. That tornadic wall cloud was very low to the ground and the use of developing tornado terminilogy would have fit perfectly. I don't care what anybody says, there was a developing tornado with that storm, it just never FULLY developed. I say that any funnel is a developing tornado. Now, whether it fully develops or not is another story.

[Danny Neal]

A few simple changes to the text can solve this dispute.....

OLD: "XXX indicates a developing tornado"


OR

SOLUTION: "XXX indicates a rapidly rotating wall cloud producing a numerous funnel clouds....a tornado may be imminent" / "XXX radar indicates a T-storm capable of producing a tornado" Its never a bad thing to be overly specific. Although when typing up the warnings I suppose you need to be as quick and precise as possible.

I guess using the phrase "indicated a developing tornado or spotters indicate a developing tornado" is such normal terminology that most people don't think too much into it. Although like numerous people have elluded too that could mean mid level/low level/funnel/actual dust whirl.

[Darren Addy]

I think it is worth noting that Greensburg was wiped out less than three weeks prior to this "event". In the wake of an F5, multiple fatalities, and the highly publicized destruction of a County Seat - even with the superb warning time given by the DDC office — I think that we can forgive NWS employees who may err on the side of caution and passing along any information that might lead to someone's life being saved. I doubt that there is time for a tremendous amount of debate and filtering, under the circumstances.

Certainly we can argue that if the public is going to take warnings seriously, we can't OVERPLAY events either (desensitizing them), but let's not forget how fresh Greensburg is in the minds of (not just the public) but the people on duty in the NWS offices across the country.

[David Drummond]

I tell you what, the best instance of a "DEVELOPING TORNADO" that I have ever seen was over the town of Stinnett yesterday. In the 10 years of chasing for me, I have never seen such rapid tornadic rotation without actually producing a tornado. That tornadic wall cloud was very low to the ground and the use of developing tornado terminilogy would have fit perfectly. I don't care what anybody says, there was a developing tornado with that storm, it just never FULLY developed. I say that any funnel is a developing tornado. Now, whether it fully develops or not is another story.

Actually it did go ahead and produce after it moved off NE of Stinnett. I managed to get part way down a backroad there and got a glipse of the edge of it, which looked to be pretty large, for about a minute before it disappeared into the rain.

As as certian fire chief I was was under once told me, "...when it comes to protecting people, it's better to overreact than to undereact."

[scott r currens]

Remember that a tornado is the wind, not the cloud. Funnel clouds touch down but tornadoes do not. A low-level circulation becomes a tornado when it contracts to the point that the wind speed reaches EF-0 criteria. Sometimes that involves condensation/debris at the ground, sometimes it does not. If condensation/debris is not present at the ground then visualy it is impossible to really know exactly when the circulation is strong enough to be considered a tornado. I say "developing tornado" when I strongly suspect that a circulation has reached EF-0 (65-85mph winds) but I don't have conclusive evidence. Many times this strong circulation “Developing Tornado” does not develop a debris cloud or condense to the ground before it weakens, other times it does. In my mind this is a bigger threat than your average rotating wall cloud, so I would report it as a possible or developing tornado.

I know what I have written is somewhat confusing so please view the following video clip to see what I mean by “developing tornado”. It is a long clip that goes back and forth between three tornadic circulations. The middle circulation is the one that applies to this discussion. It's low hanging cloud mass had strong rotation for 10 minutes before it ever condenced to the ground.

http://www.violentplains.com/video/ScottCurrens20070423b.wmv

[Mikey Gribble]

The example Scott posted is exactly what I was talking about. That is just as likely, if not more likely, to become a tornado as any funnel is and reporting it as a rotating wall cloud would be an understatement. Lots of tornadoes form before there is a recognizeable funnel coming down from the cloud base. In circumstances like this I think calling it a "developing tornado" is accurate and appropriate. When you see rapid rotation and vertical motion that close to the ground it is more than likely going to become a tornado and reporting it as a "rotating wall cloud" just doesn't convey the seriousness of the situation.

[Kory Hartman]

Various lines from the 1998 Spencer, SD NWS Asssessment:

(Keep in mind this was 9 years ago, before I-pods, satellite radio, and 800 DirecTV channels... and before additional wx radio transmitters were commissioned):

From all accounts obtained by the Service Assessment Team, the dissemination of critical severe weather information through the commercial media was excellent. Most of those in Spencer who were aware of warnings and ongoing severe weather received information through the commercial media. Sioux Falls television stations and two commercial radio stations in Mitchell were mentioned most often by those interviewed, however, other radio stations in the area, including those in Sioux Falls and Yankton, also played valuable roles in disseminating warnings.

The cable television provider for Spencer has 95 subscribers in town, however, there was no cable override system for local emergency management access.

Several residents of Spencer who knew the radio frequency used by local storm spotters kept themselves informed on the approaching tornado by listening to the spotter traffic on a scanner.

The NWR coverage on May 30 was not adequate to ensure reliable reception of severe weather information on standard, home-use receivers in Spencer.

In spite of the devastation inflicted on Spencer, many residents obtained sufficient warning information through media sources or by first-hand observation and avoided death or serious injury by taking appropriate precautions. There was, however, a significant segment of the small population who remained uninformed until the destruction began. With the volunteer fire department siren not functioning and the nearest NWR station essentially out of range, the only practical, readily available sources of warning information for most Spencer residents were television and commercial radio.

The Spencer tornado occurred when many people were watching television. Viewers in Spencer who were tuned to a Sioux Falls station were provided information on the 8:12 p.m. Tornado Warning for northern Hanson County and the 8:32 p.m. Tornado Warning for northern McCook County.

Residents who heard some type of warning in time to take precautions indicated Sioux Falls television stations or commercial radio stations as their source of warning information. Several residents of the area cited two radio stations in Mitchell, which included listener reports with warnings from NWSFO Sioux Falls.

[Gabe Garfield]

Just to clarify - per the reports there were no tornadoes logged from that warning... There was an unrelated police report of a tornado with no damage on a separate cell in the county, but nothing from the warning I'm asking about.


What reports are you looking at? From SPC Storm Data:

TORNADO:
0343 15 W LIPSCOMB LIPSCOMB TX 3623 10054 (AMA)

I saw the "developing tornado" that was spoken of in the warning. It eventually became a large multiple-vortex tornado.

I will reiterate Dan Dawson's post: it was a tornado.

Gabe

EDIT:
FWIW, I agree with rdale. It's very ambiguous language and should be made more clear.

[rdale]

What reports are you looking at? From SPC Storm Data:

TORNADO:
0343 15 W LIPSCOMB LIPSCOMB TX 3623 10054 (AMA)

I saw the "developing tornado" that was spoken of in the warning. It eventually became a large multiple-vortex tornado.

The warning I was referring to said a "developing tornado" was 14 miles southwest of Lipscomb at 0333Z and moving northeast at 25mph, so a tornado at 0343Z 15W of Lipscomb wouldn't match up. The SVS issued during the warning said that the initial storm dissipated but a new cell formed west of Lipscomb...

[Joe Zemek]

Referencing the Tornado Emergency discussion, do the terms "funnel" and "low level mesocyclone" carry sufficient semantic power to motivate the public to take precautions when they as a group have become comfortable with severe weather warnings in general? Though the phrase "developing tornado" is technically incorrect, everyone seems to grasp it intuitively as a situation involving strong low level rotation. If I were to use the phrase "developing tornado" I would probably mean "descending and intensifying funnel cloud" or "intensifying rotation in low wall cloud."

How about the word "potential"? It doesn't imply that a tornado must form, only that it seems likely to observers. It's not as strong a word.

potential-->imminent-->developing-->actual

(this scheme ignores "possible" which is already used in situations where poor visibility may conceal an actual tornado--a Schrodinger's Tornado, I suppose;) ).

In a situation where a persistent funnel or rapidly rotating wallcloud hovers above the surface with no spotted debris cloud, those in the area face a threat which is probably best described to them as a developing/imminent tornado. As others have said, better err on the side of caution.

[Mike Kruze]

Certainly we can argue that if the public is going to take warnings seriously, we can't OVERPLAY events either (desensitizing them), but let's not forget how fresh Greensburg is in the minds of (not just the public) but the people on duty in the NWS offices across the country.

EDIT: I just realized that I posted this as Mike Kruze. This is Joe Nield. I am using his laptop as we are driving near OKC to visit a friend in Norman.

Actually, sociologic research has found that, by and large, the "cry wolf" syndrome does not exist. Everyone essentially goes through a five step process that determines their reaction to a warning, and this occurs, almost without fail, every time a warning takes place, regardless of the number of previous warnings or prior false alarms. The steps (and I am paraphrasing):

1) Receive the warning
2) Understand the warning
3) Verify the warning (go outside, turn on tv/radio, call a friend)
4) Personalize the warning (feel that you are threatened)
5) Take action.

As I said in the Tornado Emergency thread a couple of weeks ago, this helps depict why response is arguably the most important and, frustratingly, the least controllable link in the integrated warning system chain. That is an entire topic unto itself, however.