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shane turner
04-11-2009, 06:57 PM
I wonder why some people place so much emphasis on a tornadoes rating. Now I find myself being just as guilty of this as other people. We will have these large tornado outbreaks and not one of the tornadoes will get at least an F4/EF4 rating. It seems like we have had many cases of this over the past several years and when there is a tornado that questionably seems violent by the public or other experts there is no consideration even taken. Now construction practices must be taken into place when rating a tornado but some of the construction was described as being well-constructed and it still did not receive an F4/EF4 or F5/EF5 rating. These more recent tornadoes especially the Mena, Arkansas tornado seems to have questionable EF4 damage present. A steel-reinforced building made out of concrete and mortar being completely flattened seems really impressive. Now I am no expert but have been studying this for quite a few years. An F3/EF3 tornado is still a pretty rare tornado and are probably just as deadly as violent tornadoes. The thing I am getting at is when there is questionable EF4 or EF5 damage from the public or other experts no consideration is even taken. It also seems to puzzle me why less than .5% of all tornadoes have been rated F4/EF4 or F5/EF5 over the past ten years. Also there has not even been a tornado rated as violent during the month of April since the La Plata, Maryland tornado. Now while most of you dont care about a tornadoes rating, I tend to find myself placing a lot of emphasis on it. I also find myself upset when there is a large tornado outbreak and no tornado is rated as violent.

Keith Mullen
04-11-2009, 07:01 PM
I don't know why, and have often wondered that myself.

My personal theory is american standards: Bigger, Better, Stronger, Faster, Now, Now, Now... If it's super-sized, that means it has got to be even better right?

Just my thought on it. After living in other countries & travelling - we seem to be the only culture that applies this line of thought to everything placed in front of us.

Personally speaking, I will take a beautiful, photogenic, roping F0/1 ANY day over an HP or Low-Vis F3/4/5 any day.

...but that's just me ;)

shane turner
04-11-2009, 07:20 PM
It looks possible that the Murfreesboro tornado may get rated at least an EF4.

http://www.srh.noaa.gov/productview.php?pil=OHXPNSOHX


Even though it still makes me wonder about the one in Mena as well. I also never saw all the damage photos from the Murfreesboro tornado but it very well could go at least EF4 by the description from NWS in Nashville. From aerial views and damage photos the only thing I saw was about high-end EF3 damage in which there were entire houses that were nearly flattened. This statement seems to say it could go higher for well-built homes were swept clean off thier foundations.

Chris Nuttall
04-11-2009, 07:31 PM
It seems like we have had many cases of this over the past several years and when there is a tornado that questionably seems violent by the public or other experts there is no consideration even taken.

9 times out of 10 if someone's house is destroyed by a tornado they automatically think it has to be an EF5. How many times do you see news reports of people screaming, "A tornado destroyed my house!" only for the official report to come out that it was a downburst? My point is that the public is not trained and generally not knowledgable about how to classify damage, so, I'm not sure why you're getting all worked up about the public's opinion not being considered. Also, who are you talking about by "other experts?" People (experts included) can state their opinions about something all they want, but if they are not in the field and not on the survey team, they can only speculate.

Now construction practices must be taken into place when rating a tornado but some of the construction was described as being well-constructed and it still did not receive an F4/EF4 or F5/EF5 rating. These more recent tornadoes especially the Mena, Arkansas tornado seems to have questionable EF4 damage present. A steel-reinforced building made out of concrete and mortar being completely flattened seems really impressive. Now I am no expert but have been studying this for quite a few years.

Shane, you tend to lean toward the high-end ratings of most events. You are very concerned that tornadoes should be getting EF4 or EF5 ratings. This is not a knock on you, simply an observation. Keep in mind, there are lots of factors that go into whether something is "well constructed." You cannot determine these things from watching the news. A person has to be on-site and looking at these houses very closely. La Plata is a great example. Everyone saw the footage of damage and said, "EF5." Upon further investigation, it was found that the houses were not attached properly to their foundations, resulting in "sliders." Thus, the tornado received a lower rating.

It also seems to puzzle me why less than .5% of all tornadoes have been rated F4/EF4 or F5/EF5 over the past ten years.

For one thing, consider how many more tornadoes are getting reported in the last ten years. With the increase in the numbers of chasers/spotters and communication and computing technology, we're finding tornadoes in storms that we probably wouldn't have 10-15 years ago. The high-end events are rare, so it's logical that many of these additional tornadoes are probably going to be on the low-end of the scale, especially since most happen over open country.

Also there has not even been a tornado rated as violent during the month of April since the La Plata, Maryland tornado.

So, what do you think this means? We're overdue? The teams doing the ratings are doing a poor job? To be honest, it means absolutely nothing.

I also find myself upset when there is a large tornado outbreak and no tornado is rated as violent.

I can't seem to understand why. The size/magnitude/significance of a tornado outbreak is not (scientifically) defined by any one particular tornado's rating. The definition of an outbreak is in terms of a number of tornadoes occurring in a particular area over a certain time period. The Super Outbreak of 1974 is not "super" because of the Xenia, OH, tornado. However, these types of events can be iconified, or defined psychologically, by a single high-impact tornado that occurred during the overall event. Examples include Xenia, OH (4/3/1974); Andover, KS (4/26/1991); and Bridge Creek/Moore, OK and the often-forgotten Mulhall, OK (5/3/99).

There is an important question that everyone should ask themselves. Is a tornado's rating truly important? If a house is destroyed and someone is killed, does it matter if it was an EF2 vs. EF5, or even a tornado vs. straight-line winds? The rating is not important, but the human impact is.

People (victims included) tend to carry the rating of any event (hurricane, tornado, earthquake) as a badge of honor. They often get upset if "their event" doesn't receive the highest rating. Scientifically, it may not warrant that. But, if a tragedy occurs, does it really matter? The human impact is still the same regardless of what arbitrary number is assigned.

mikegeukes
04-11-2009, 07:56 PM
This may explain, why the tornadoes in the past were rated higher.

"The Nuclear Regulatory Commission (NRC)
supported the NSSFC in reviewing over 17,000
tornado reports in the Climatological National Data
Summary and Storm Data between 1950 and
1976 to develop tornado climatology in the United
States The NSSFC employed the services of
students in each state to review available local
databases and cross reference newspaper articles
to assess the tornado damage and assign the
appropriate F-scale. The NRC also supported Dr.
Ted Fujita at the University of Chicago to develop
a tornado database."

Shane this article may of be of interest to you.
http://www.spc.noaa.gov/publications/mccarthy/f-scale.pdf

Once again some folks put too much emphasis on the rating tornadoes.

Mike

shane turner
04-11-2009, 08:03 PM
I know what you mean but at times I have called NWS offices and some have said to me that they considered a higher rating but did not for whatever reason. This could be from something being damaged such as a large well-built home I saw with anchor bolts and lugs on the bolts. This house was completely flattened but somehow the tree nearby sustained minimal damage so they went with a lower rating. Yes I do place a lot of emphasis on the ratings and should realize its just a number. I tend to lean toward EF3 or EF4 events as long as they dont rate tons of a tornadoes high-end EF3 and not a single one an EF4. Now an EF5 tornado sometimes seems to be almost impossible to even put emphasis on it and there has to be overwhelming evidence to rate a tornado as such. Yes I tend to like more of the stronger type tornadoes. I feel like like I have to wait many days out of the year for such events to happen and when a large tornado outbreak happens and not a single tornado is rated as violent I get very disappointed.

Jason Boggs
04-11-2009, 08:08 PM
It also seems to puzzle me why less than .5% of all tornadoes have been rated F4/EF4 or F5/EF5 over the past ten years.

EF4 and EF5 tornadoes are how I like my steak,,,RARE!

Angie Norris
04-11-2009, 10:37 PM
I think the origin of the practice of rating tornadoes was for climatological statistics and to refine building codes and practices.

I think the last thing we want to see as chasers and meteorologists is the deaths that any weather phenomena can and do cause, because it almost seems like we are failing on one level, as in not getting the word out as to how people can and should protect themselves. We can't do anything about the property destruction that storms can cause, since we have to live somewhere, and people who live in high risk areas understand and accept the risk.

As chasers we walk an extremely fine line; we all like to witness the once in a lifetime event that each storm is, and we enjoy experiencing the adrenaline rush that experiencing the ultimate power that is the atmosphere in action. BUT do any of us take pleasure in witnessing the destruction caused? I seriously hope not. If that is the case, that individual is in serious need of help. There is a huge difference between the immense power of a huge wedge roaming the open plain causing no damage, and that same storm destroying lives and property. EF-0s can and do kill when they impact communities. Does that make them less significant? I don't think so...ask the families of the victims.

Ratings are nothing other than data sets that allow statisical analysis. Why should we glorify a data set?

Darren Addy
04-12-2009, 12:00 AM
I've said this before, but this thread is starting from the incorrect premise that tornadoes are being rated.

It is hard for people to wrap their minds around this, but the scale is a damage rating - not a tornado rating. I think a good analogy would be the medical rating for burns. You have 1st degree, 2nd degree, and 3rd degree burns (and you have them over a certain percentage of your body). The damage of the burn doesn't say a lot about the severity of the actual heat that caused the burn. The damage is a combination of the heat and the proximity and the time in contact with the skin.

Similarly the EF/F scale is rating the damage, which tells us some things about the originating tornado, but not everything. As humans we want to classify everything and so we think we are classifying tornadoes, but we are really only classifying the thing we can wrap our arms around: the resulting damage.

Danny Neal
04-12-2009, 02:22 AM
Just a quick observation.... You are upset that there are barely any violent tornadoes? So you like the devastation and loss of life? I feel like like I have to wait many days out of the year for such events to happen and when a large tornado outbreak happens and not a single tornado is rated as violent I get very disappointed. I mean..... seriously?!?

Shane Adams
04-12-2009, 02:30 AM
Ratings mean nothing. After all, we tossed out 36 years of research, teachings, and application back in 2007. As our technology advances, so will the changes to our ways of thinking. In 2007 I predicted a second change to the F-scale within the next decade, because it will only take us 1/3 of the time by today's standards to figure out we're still wrong. I guess when that happens it'll be the "EEF" scale (Extra-Enhanced Fujita).

I have to wonder, after reading several of your posts, if you're not more interested in why tornadoes aren't rated higher then you are tornadoes themselves.

shane turner
04-12-2009, 09:06 AM
No Danny I do not like to see devastation or loss of life due to any type of tornado. I am however very fascinated by the awesome power of what a violent tornado can do to a community within a matter of minutes. I find it very disappointing when people lose everything they have to a tornado and people are killed and injured as well and the tornado only receives like an EF3 rating due to flimsy construction. I wish nobody got killed by tornadoes at all but unfortunately it happens every year despite on how much warning is provided.

Greg Stumpf
04-12-2009, 09:29 AM
Just a quick observation.... You are upset that there are barely any violent tornadoes? So you like the devastation and loss of life? I mean..... seriously?!?
I understand Shane's point - he is concerned that some tornadoes aren't being rated as judiciously as others. Tornadoes should never be mis-rated, or prevented from being properly rated, to satisfy some non-scientific, and usually political, reasons.

Ratings mean nothing. After all, we tossed out 36 years of research, teachings, and application back in 2007. As our technology advances, so will the changes to our ways of thinking. In 2007 I predicted a second change to the F-scale within the next decade, because it will only take us 1/3 of the time by today's standards to figure out we're still wrong. I guess when that happens it'll be the "EEF" scale (Extra-Enhanced Fujita).
You misunderstand the primary objectives of the EF scale. The scale is designed to be "living". The wind speed estimates tagged to various damage indicator's (DI) degrees of damage (DOD) originate from various levels of knowledge and understanding of the effects of violent winds on those DIs. What the EF scale allows is the refinement of those wind speed estimates as the science evolves. It also allows for the addition of new damage indicators and associated wind speed estimates. I see the EF scale not as a change in the wind speed estimates, but rather as a change in the process by which we rate tornadoes. Properly applied, what should be recorded are the DIs and DODs, not the wind speeds. With the DI/DOD data, one can apply the most contemporary wind speed estimates to those data.

The EF scale is a natural evolution of the F scale. The F scale had very few DIs (single- and double-family residential homes dominated the scale), and the wind speed estimates for those DIs were revised to the first version of the EF scale. Nothing was "tossed out" as you say.

Dean Baron
04-12-2009, 09:33 AM
No Danny I do not like to see devastation or loss of life due to any type of tornado. I am however very fascinated by the awesome power of what a violent tornado can do to a community within a matter of minutes.

That seems pretty contradictory.

Every time I have seen someone complain about a tornado's rating it has been you Shane. Why you care so much about these ratings I dont know, but as has been said before, rating dont mean much.

Darren Addy
04-12-2009, 09:55 AM
Remembering that this is the beginner's forum, I think we should all watch our tone with Mr. Turner here. I think he is expressing (a bit clumsily perhaps) a frustration that all tornado afficianados share, which is our inability to accurately measure the relative strengths of tornadoes. Even if we could accurately measure wind speed, you have the debate over whether a tornado that is twice as wide is "rated stronger" than a tornado that has higher windspeed, but affects a narrower path. Add onto that the storm speed. A tornado with windspeeds moving at 20 mph is going to do a lot more damage than one moving at 50 mph. Add to that damage caused by winds loaded with debris. (The strength of the tornado has not changed, but it is now carrying "schrapnel" which is going to do a lot more damage than the wind by itself).

All of this should explain why trying to put a simple strength label on a tornado is folly. All we can do is rate the damage that is left. But that does not say that your tornado was definitely "higher on the charts" than the one that stayed on the ground for 50 miles in the middle of Cherry County Nebraska hay territory and hit next to nothing.

A "real" formula would have to take into account the diameter/area of the tornado, the tornado's windspeed, the speed at which the tornado was moving along the ground, and somehow account for how "loaded" the debris cloud was... to accurately "compare" tornadoes. Since we can't really accurately measure at least two of those parameters, it is sort of a moot point.

I think we all share Danny's inherent fascination with the power of tornadoes, and we all hate to see human lives and property impacted, but when it happens I think we all share a fascination with looking at the resulting damage survey and (for example) the weird things that seem to be left untouched while other things are gone.

Humans like to label/classify and things and put them in their own little boxes. It gives us some sense of assigning order to chaos. But don't confuse having a sense of chaos with actually having a firm handle on chaos. That is all EF ratings do, as far as giving an accurate picture of the strength of the originating tornado (as opposed to its resulting damage).

Danny Neal
04-12-2009, 10:52 AM
No Danny I do not like to see devastation or loss of life due to any type of tornado. I am however very fascinated by the awesome power of what a violent tornado can do to a community within a matter of minutes. I find it very disappointing when people lose everything they have to a tornado and people are killed and injured as well and the tornado only receives like an EF3 rating due to flimsy construction. I wish nobody got killed by tornadoes at all but unfortunately it happens every year despite on how much warning is provided.

After re-reading your post this morning, perhaps I overlooked your fascination with the actual rating/deciphering (of) the damage, and not so much that the damage occurred. For that I apologize! I guess I share the same fascination to an extent. Of course seeing destruction is never easy and I am sure we both can agree on that. But once it has happened and it is out of our hands, I believe you have a real knack for trying to interpret what occurred, why it occurred, how it occurred and etc.

I understand Shane's point - he is concerned that some tornadoes aren't being rated as judiciously as others. Tornadoes should never be mis-rated, or prevented from being properly rated, to satisfy some non-scientific, and usually political, reasons. A side I didn't really think of. My first impression was "damage junkie" almost like he was rooting the wedge to hit the large city which I think we would all agree poses a bit of a problem. However, after re-reading several of his posts in the past (mostly on the EF-scale) I got a feel for what he's talking about and his excitement with ratings and classifications. It is a topic I probably overlook time in and time out. Once a rating is given that's it in my eyes, I never had the will to look into it and figure out why this was rated an (E)F3 and not a 4. Now that I have gotten my hands in building construction within the last year or so (big part of fire service is knowing your enemy I.E. fire and the building) I think I should start reading up on past surveys and newer surveys for that matter, not to judge but to understand what happens in a total building collapse, partial, the fundamentals of the building, and etc.

Greg you out of anyone would know about the non-scientific and political reasons as you are elbow deep into the development and continuance of the EF Scale. It is a shame such things occur and I admire yours and everyone else tenacity involved in keeping the scale effective.

I think we all share Danny's inherent fascination with the power of tornadoes, and we all hate to see human lives and property impacted, but when it happens I think we all share a fascination with looking at the resulting damage survey and (for example) the weird things that seem to be left untouched while other things are gone.

Humans like to label/classify and things and put them in their own little boxes. It gives us some sense of assigning order to chaos. But don't confuse having a sense of chaos with actually having a firm handle on chaos. That is all EF ratings do, as far as giving an accurate picture of the strength of the originating tornado (as opposed to its resulting damage)

I agree with you. As I said, I may have mis-judged what Shane was getting at. As I said above, upon first read it was like he was pissed off because more violent tornadoes don't occur and I guess I drew the comparison to violent tornadoes = loss of property or life and that's something I absolutely can not stand to see. :D Perhaps I shouldn't post at 2 A.M. anymore when I am half asleep.

Again Shane, apologies to you and my goal wasn't to rake you over the coals, but just a poor attempt at trying to understand what you were saying.

shane turner
04-12-2009, 11:16 AM
I accept your apology Danny and thank you everybody for the comments. Even though I think a tornado should get rated higher or lower than it actually is, is not for me to say. It has to be a tedious process when doing a survey on site. Sometimes tornadic damage photos at times seem to be questionable when I look at detailed damage photos posted. I guess everybody has an opinion and yes I am obsessed with rating tornado damage. I did the EF-kit online and did pretty well. Now most of those photos on this site seemed pretty accurate but a few seemed a little bit too low or too high in my opinion.

Wes Carter
04-14-2009, 06:23 PM
Shane, I'm somewhat of a newbie myself so take what I'm saying with a grain of salt. But since this forum is open to all ideas I'll throw mine out there to get torn apart. :) You probably know most of what I'm describing but because this is the beginner's forum I want to make sure that everyone can latch on to my main point.

The Enhanced Fujita scale is just a tool that is used in the study of tornadoes. It is an attempt to determine the relative strength of a tornado based on the damage it did. Unfortunately Dr. Josh Wurman and the Doppler On Wheels truck cannot be at every tornado to directly measure tornado wind speed.

It is much more likely that there will be things in the path of the tornado that can be used to make an educated guess of the wind speed of the tornado. But it's not guaranteed that those things will be in place. And it can be difficult to determine how well a home was constructed once it is completely gone.

If a tree falls in the woods and no one is there to hear it does it make a sound? We have all heard that silly question but for tornadoes there is a similar question. If a tornado occurs and it only hits fields, trailer parks, poorly constructed homes, etc... then how do we properly classify it? We really can't. If a tornado with 250MPH winds hits nothing but a wheat field it might not be rated at anything more than an EF-0 or EF-1.

Because the EF rating is given days AFTER the tornado has passed the EF scale should have little to no affect on how seriously the public takes tornado warnings. I keep my 2 meter radio on during severe weather events and I have never heard a spotter say, "It appears to be a weak tornado." I have heard many times "It is a large and very powerful tornado!" In the Murfreesboro tornado last Friday I heard that same report and took it with a grain of salt. It turns out they were right this time, but I have heard the same report when the tornadoes turned out to only be classified as EF-1's.

My main point is this: The EF scale should not have too much emphasis placed on it by the general public. It is a very useful tool for science and engineering but really for the rest of us it simply is something that fulfills a human need to put everything in a categorized box as Darren Addy pointed out before. Don't let the details bother you on this one. We need to treat all tornadoes with respect. They are all awesome.

Interesting read:
http://www.spc.noaa.gov/faq/tornado/ef-ttu.pdf

shane turner
04-14-2009, 08:23 PM
Here is another reason to not always place emphasis on a tornadoes rating. Lets say a mile-wide EF5 tornado with a 20 mile track touches down in a rural area and blows a well-built brick home off its foundation, turns tractors and vehicles into unrecognizable fragments, and strips trees of all their bark. Lets say this tonado killed no one or caused no injury because it stayed out in mainly rural area. Now lets also say a 1/4 mile wide EF2 tornado stays on the ground for 15 miles and goes through a fair ground packed with thousands of people, causes significant damage, kills 50-100 people, and injures hundreds of others. I would hope the EF2 tornado would receive more publicity than the EF5 tornado. A weaker tornado can be just as deadly a stronger tornado.

John Wetter
04-14-2009, 10:26 PM
I guess I'm failing to see where this conversation is going... A tornado is rated on the severity of the damage, not the impact. The news shows things on a scale of impact, not necessarily damage. The whole point of the EF scale is to assign scientific quantifiable levels to things, the DI's. So, yes, a weak tornado in a populated area will almost certainly get more press than a monster in the middle of nowhere... Impact vs. strength.

Robert Hurkes
04-15-2009, 09:24 AM
Besides the OP, who is putting such large emphasis on a tornado's rating? As others have mentioned, its just a quantifiable way of trying to measure and categorize each tornado's damage. I'm not aware of anything like this, but does the EF classification of a tornado have anything to do with federal or state aid?

Obviously, more powerful tornadoes are more likely to:
a) be seen
b) come from cells that get the attention of many chasers/spotters
c) have an impact on human life
d) be rare

Based on those 4 criteria, higher-rated tornadoes will be more of an "event", whether you're a chaser looking to fill in the EF5 slot on your chase card, an emergency worker trying to rescue people trapped under a torn-apart building, a homeowner who no longer has a home, or someone helping to rebuild after a town has been leveled. I won't comment any further on this, as I don't want to derail things into a discussion of altruism.

Bob Hartig
04-15-2009, 10:59 AM
It's human nature to view tornadoes with emotion. As someone pointed out earlier in this thread, our culture is one that loves extremes and attaches value to the Biggest and Baddest. Because of this emotional component, a fair portion of the public has historically viewed--and will continue to view--the F and EF scales as a sort of "award."

But the EF scale isn't about pinning medals on certain storms or outbreaks while declaring other tornado events as also-rans. It's simply a tool, a yardstick for measuring tornado damage. A yardstick is objective. An inch is an inch and a foot is a foot, and if you stand up next to a yardstick and it says that you're five-foot-ten, then there's no point in insisting that you're six-foot-four. Granted, the analogy breaks down in that a yardstick is a simple tool with a simple application, where the EF scale is a sophisticated tool designed to be applied in complex scenarios that require a greater degree of human judgment. But the general idea still holds water.

I witnessed my first violent tornado last year. To say it was violent is different than saying it was an EF4 or an EF5. It wasn't; it was an EF3. Had it impacted the town of Hazleton, IA, head on instead of striking it a glancing blow, I suspect the EF rating would have jumped a notch. But in view of what the EF ratings imply in terms of human impact, I'm glad the Hazleton tornado was "only" an EF3. It didn't require a medal for it to have been an impressive and fascinating storm. I got to see it, and the reward of that experience was enough for me.