Strongest tornado of 2010

[Mike Kovalchick]

Without going into much detail, as I don't know if I can, there were some very interesting measurements taken at basically ground level or just above ground level (2ft AGL, .7 meters or so) by the twistex team on the Bowdle wedge.
Winds were in excess of 130mph....makes a guy wonder how strong they were at 30ft?!?!? Of course Shane and the others are right, it is hard to tell which tornado may have been stronger but visually Bowdle wins in my book!

Great discussion BTW!

130+ mph inflow at 2 feet above ground? (You would think perhaps 200 mph at the top of the boundary layer?) Yikes! No wonder I felt like Moses standing in front of the Dead Sea when it was parting while watching that tornado! I can't believe some are voting for that Yazoo glorified rotating rain storm as the strongest tornado. If you subtract the forward speed of it, the core winds wouldn't even match the inflow into the Bowdle wedge which was nearly stationary at times.

The only reasonable argument for the Yazoo wedge is considering intensity X distance on the ground suggesting a very high level of total energy expended during the life cycle far exceeding the Bowdle wedge.

Looking at it another way, suppose you have a weight lifter who could bench press 1000 pounds for one rep. Then you have a runner who carries 25 pound weights while he jogs 50 miles. Who would win the strongest man contest? The weight lifter of course! Same logic should apply to the Bowdle wedge.

 

[Adam Lucio]

As someone mentioned, given the fact Yazoo had a much larger damage swath the intensity was probably well represented in the survey. Even if structures weren't hit there were still plenty of trees to be mowed over which can indicate strength as well.The same can't be said for the Bowdle wedge.

Even after Greensburg there has been speculation that the same supercell dropped an even stronger tornado afterwards, it just didn't hit anything substantial. IMO this is one of the reason to keep studying and discussing tornadoes, especially significant ones to determine their true strength.

 

[Shane Adams]

I find it interesting that the Yazoo tornado is being scoffed at for its forward speed, while the Bowdle tornado is being supported because it was basically a stationary "grinder."

Years ago, there was a debate amongst the weather/science community regarding the Jarrell, TX tornado of May 27, 1997. It received an F5 rating of course, but many big names disagreed with that rating. They pointed to the fact it was basically stationary, sitting over the same structures for extended time just grinding away. They speculated the tornado was only F3 strength, but caused F5 damage because of the constant grinding (in other words, F3 winds can do F5 damage if structures are subjected to it continuously).

I can understand their point of view and argument, but what always confused me about it was the fact they were basically ignoring the F-scale and basing their opinions on either visual or radar data...i.e., making the (guesstimated) windspeeds their main focus. Because we have been constantly preached to by the wx/science world that the F scale is a damage scale, not a windspeed scale, I always found that Jarrell argument to be odd.

Now, years later, I'm reading how some individuals have the reverse opinion; a stationary tornado that is a grinder is considered more powerful than a fast-moving tornado, whose core winds (without the forward motion) are being either (1) wrongly under-estimated or (2) ignored completely.

Lastly, on a personal note, "glorified rotating rain storm" probably wouldn't fly with many folks from the Yazoo City area, as expressed on this thread. We, as chasers, especially in this "greatest video of all-time, every time" generation, are too quick to dismiss a tornado because it did not satisfy our sensory, aesthetic needs. There's a lot more to a tornado than a chaser's opinion.

 

[ChristianTerry]

Wondering what anyone thinks about the strength of the Howes/Faith SD tornado? They were pretty strong too.

 

[Nick Nolte]

Wondering what anyone thinks about the strength of the Howes/Faith SD tornado? They were pretty strong too.

Being on both the Howes and Bowdle storms, I would say the Howes tornado doesn't hold a candle to the Bowdle wedge. I did not catch the one NW of Faith.

It was pretty photogenic, it's the one I'm walking towards in my avatar. It also received an EF-2 for destroying a pole barn and a manufactured home, but I wouldn't be surprised if was actually stronger as it plodded through the field south of the highway 34, but in my humble opinion it was pretty far removed from the power of Bowdle and Yazoo.

 

[ChristianTerry]

Being on both the Howes and Bowdle storms, I would say the Howes tornado doesn't hold a candle to the Bowdle wedge. I did not catch the one NW of Faith.

It was pretty photogenic, it's the one I'm walking towards in my avatar. It also received an EF-2 for destroying a pole barn and a manufactured home, but I wouldn't be surprised if was actually stronger as it plodded through the field south of the highway 34, but in my humble opinion it was pretty far removed from the power of Bowdle and Yazoo.

Judging from the photos, I think the Bowdle one was far stronger. I wasn't there so I don't know. Im only a kid so I can only ask questions.

 

[Jeff Duda]

I find it interesting that the Yazoo tornado is being scoffed at for its forward speed, while the Bowdle tornado is being supported because it was basically a stationary "grinder."

Years ago, there was a debate amongst the weather/science community regarding the Jarrell, TX tornado of May 27, 1997. It received an F5 rating of course, but many big names disagreed with that rating. They pointed to the fact it was basically stationary, sitting over the same structures for extended time just grinding away. They speculated the tornado was only F3 strength, but caused F5 damage because of the constant grinding (in other words, F3 winds can do F5 damage if structures are subjected to it continuously).

I can understand their point of view and argument, but what always confused me about it was the fact they were basically ignoring the F-scale and basing their opinions on either visual or radar data...i.e., making the (guesstimated) windspeeds their main focus. Because we have been constantly preached to by the wx/science world that the F scale is a damage scale, not a windspeed scale, I always found that Jarrell argument to be odd.

Now, years later, I'm reading how some individuals have the reverse opinion; a stationary tornado that is a grinder is considered more powerful than a fast-moving tornado, whose core winds (without the forward motion) are being either (1) wrongly under-estimated or (2) ignored completely.

Lastly, on a personal note, "glorified rotating rain storm" probably wouldn't fly with many folks from the Yazoo City area, as expressed on this thread. We, as chasers, especially in this "greatest video of all-time, every time" generation, are too quick to dismiss a tornado because it did not satisfy our sensory, aesthetic needs. There's a lot more to a tornado than a chaser's opinion.

Shane I think you have broached the core of this debate. Meteorologists and chasers frequently use the (E)F-scale interchangibly with the term "strength" to judge the "UMPH! " - factor of tornadoes. There is a fundamental difference between the true, objective "strength" of the tornado (which to my knowledge does not yet have a scale by which to be measured), and the scale used to judge the damage. What is always there trying to glue this apples vs. oranges rift together is the fact that the EF-scale includes wind estimates, which most people assume is an excellent proxy for "strength". While that may be, there are the other facts that you brought up, Shane, that clearly have not been addressed in the current EF-scale, but clearly have an impact on what the EF-scale measures (which is damage) - and that is "duration". How will the amount of damage to a structure change with duration of a given wind speed? Will a single family house being exposed to 100 mph winds for 20 seconds suffer the same amount of damage as that same house being exposed to 150 mph winds for 12 seconds? Obviously the wind speed affecting a structure will change more or less continuously with time, so probably the wind speed should be integrated (summed) over the entire duration of the tornado's passage of the structure to get a better "estimate". However, I honestly have no idea what this difference in damage with duration could be. It may be too complicated to be practical as well. I don't know.

Despite what I've just said, due to my posts earlier in this thread, it is obvious that I mistakenly interchange damage with strength as well. It's easy to forget when in the heat of the moment chasing or debating.

 

[Bob Hartig]

Shane, I think you're spot-on about a number of things. As for the Yazoo City tornado, I would take exception to lightly dismissing it. Check out the SRV that L.B. LaForce provided--that's no wimp of a mesocyclone. And while I agree with Mike about the importance of forward momentum in *speculating* about that storm's potential--I've already discussed that issue in a previous post--I want to point out that, from what I understand, EF-4 structural damage occurred on the northern (and theoretically weakest) part of the tornado, where translational speed was less of a factor. My personal feeling was that the Bowdle wedge was the more innately powerful tornado, but the Yazoo tornado was hardly a bantamweight.

 

[Adam Lucio]

Also one must consider the debris and projectiles. If you take the same tornado, move it over an open field where it picks up nothing and slam it to a house, the house will have some degree of damage based on the strength.

Now, if you take that same tornado and that same house and add other houses in-front of it you now have projectiles that can bombard the house and do further damage.

again, both Yazoo and Bowdle seem to have been in opposite scenarios here.

I can see how the forward speed of the tornado doing damage could be argued....but using that same argument I could come out and say was Greensburg really an EF-5 or was it really just a 2 mile wide EF-3 because it took that tornado a couple MINUTES to move over any one given structure where the worst damage was found. Now Im not trying to downplay any of this event but Im just using the same logic Ive read here and applying it to a different case

 

[Mike Kovalchick]

Shane, I think you're spot-on about a number of things. As for the Yazoo City tornado, I would take exception to lightly dismissing it. Check out the SRV that L.B. LaForce provided--that's no wimp of a mesocyclone. And while I agree with Mike about the importance of forward momentum in *speculating* about that storm's potential--I've already discussed that issue in a previous post--I want to point out that, from what I understand, EF-4 structural damage occurred on the northern (and theoretically weakest) part of the tornado, where translational speed was less of a factor. My personal feeling was that the Bowdle wedge was the more innately powerful tornado, but the Yazoo tornado was hardly a bantamweight.

"Check out the SRV that L.B. LaForce provided--that's no wimp of a mesocyclone."

Yes indeed! In fact, if your overlay that with the reflectivity images..it paints a picture of something more akin to a meso or miso scale hurricane.(Maybe that is more descriptive than a glorified rotating rain storm?) I believe it probably belongs to the same family of phenomena that includes the infamous Tri-State tornado.

By defintion, strong means great physical power.

Power is defined amount of work performed during a period of time.

Work is amount of energy transferred by a force acting through a distance.

With all of that in mind, I believe the amount of wind energy present/ aerial size/ and duration all should be combined into determining how "strong" a tornado really is.

For the arguments I made previously, the correct duration to use probably isn't the whole life cycle of a tornado..but some finite period...say for argument's sake..a ten minute period that the tornado is at it's most violent stage.

 

[Kevin Walters]

I find it interesting that the Yazoo tornado is being scoffed at for its forward speed, while the Bowdle tornado is being supported because it was basically a stationary "grinder."

Years ago, there was a debate amongst the weather/science community regarding the Jarrell, TX tornado of May 27, 1997. It received an F5 rating of course, but many big names disagreed with that rating. They pointed to the fact it was basically stationary, sitting over the same structures for extended time just grinding away. They speculated the tornado was only F3 strength, but caused F5 damage because of the constant grinding (in other words, F3 winds can do F5 damage if structures are subjected to it continuously).

I can understand their point of view and argument, but what always confused me about it was the fact they were basically ignoring the F-scale and basing their opinions on either visual or radar data...i.e., making the (guesstimated) windspeeds their main focus. Because we have been constantly preached to by the wx/science world that the F scale is a damage scale, not a windspeed scale, I always found that Jarrell argument to be odd.

Now, years later, I'm reading how some individuals have the reverse opinion; a stationary tornado that is a grinder is considered more powerful than a fast-moving tornado, whose core winds (without the forward motion) are being either (1) wrongly under-estimated or (2) ignored completely.

Lastly, on a personal note, "glorified rotating rain storm" probably wouldn't fly with many folks from the Yazoo City area, as expressed on this thread. We, as chasers, especially in this "greatest video of all-time, every time" generation, are too quick to dismiss a tornado because it did not satisfy our sensory, aesthetic needs. There's a lot more to a tornado than a chaser's opinion.

Very well stated Shane. The argument to ignore the forward motion of certain tornadoes when attempting to compare potential strength between different tornadoes makes little sense to me. The storms in the Super Outbreak, Palm Sunday, as well as many others were cranking along at 50+mph. Obviously different environments exist for different violent tornadoes, however the end result as far as damage (potential damage) is similar.

 

[Mike Kovalchick]

Very well stated Shane. The argument to ignore the forward motion of certain tornadoes when attempting to compare potential strength between different tornadoes makes little sense to me. The storms in the Super Outbreak, Palm Sunday, as well as many others were cranking along at 50+mph. Obviously different environments exist for different violent tornadoes, however the end result as far as damage (potential damage) is similar.

I think he missed the point of the recent discussion. The Bowdle wedge was doubly impressive as much of its wind energy was not as a result of it's translational speed as in the case of the Yazoo wedge. Bowdle appeared to be capable of producing incredible wind speeds(and hence damage) without any extra help either through fast, slow or stationary forward motion. Yes..forward motion is part of the tornado wind component and should be considered in how strong a tornado is. The Yazoo tornado with rapid forward mortion had plenty of opportunity to create F5 damage along it's path but failed to do so. The Bowdle wedge didn't have the same chance.

The final consideration is the actual aerial coverage that sustained the highest wind energy when the tornado was at it's most violent phase during a defined interval of time. I would have to go back and look at the track widths of both storms. I think Bowdle was at a mile wide but that may have been after it reached it's peak intensity. Yazoo I think was an incredible 1 3/4 miles wide but again I'm not sure what the rating was when it was that wide. If the Yazoo was at maximum intensity when it was that wide, then perhaps I would consider changing my vote? (Of course-we all know that in a given damage path-the actual wind energy/damage could be highly varied due mostly to suction vortices or the lack there of.)

 

[Dean Baron]

I have to say I dont think a longer duration of a tornado on an object will increase the severity of the damage to the object (i.e. I dont think a tornado with EF3 winds that sits over a house for a long duration will cause the damage to become EF4 damage because of the long duration). This is the example I have, and I may be off-base here so maybe the engineers and physicists can chime in. A tornado with EF3 winds that impacts a car will, for no matter how long a duration, be able to pick up and throw that car because it takes energy equal to or greater than a specific amount of energy (I have no idea what amount that is) to lift that car and toss it. It doesnt matter how long that tornado impacts that car because as long as it does not increase in intensity, it will never have the energy required to pick up and toss the car. If this doesnt make sense I can try to come up with another example of what I'm trying to explain.

 

[Wes Carter]

What I don't understand is why should we ever dismiss a tornado's stregnth because of it's forward speed or lack of it? It doesn't matter if a tornado is screaming along at 70mph and that forward speed enhances the damage on the southern flank OR if it instead sits there and grinds away for a minute. If the question is which one was more powerful with respect to the damage they are capable of (which is what we are ultimately concerned with) then the forward speed of the tornado is just a component of why one was more powerful, not a determining factor of whether or not it was more powerful.

Although I don't agree with Mike's assessment of the Yazoo City tornado as a "glorified rain storm", especially with the human impact of the storm, he did remind me of something I have thought about quite a bit. I live in Southern Middle Tennessee and looking at maps of powerful tornadoes, us in Northern Mississippi, Northern Alabama, and Middle Tennessee seem to have more than our fair share of powerful tornadoes (F-3 and above). I think that if you take almost any tornado that occurs in the Great Plains that did not hit a highly populated area and put it almost anywhere in the Southeastern US it will get a higher rating just because it is more than likely going to hit something and the surveyors will have a much easier time assigning it a rating. I don't think that tornadoes in the Southeast are overrated as much as I think many (if not most) tornadoes in the Great Plains are underrated because during the tornadoes most powerful stretch there is a very good chance it's just going to be churning in a field.

My point has probably been made a thousand times before but I think that this discussion is one that perfectly illustrates it.

BTW, It's awesome to see some really good civil discussion on what could potentially be an emotionally charged debate.

 

[MatthewCarman]

I have to say I dont think a longer duration of a tornado on an object will increase the severity of the damage to the object (i.e. I dont think a tornado with EF3 winds that sits over a house for a long duration will cause the damage to become EF4 damage because of the long duration). This is the example I have, and I may be off-base here so maybe the engineers and physicists can chime in. A tornado with EF3 winds that impacts a car will, for no matter how long a duration, be able to pick up and throw that car because it takes energy equal to or greater than a specific amount of energy (I have no idea what amount that is) to lift that car and toss it. It doesnt matter how long that tornado impacts that car because as long as it does not increase in intensity, it will never have the energy required to pick up and toss the car. If this doesnt make sense I can try to come up with another example of what I'm trying to explain.

If a tornado hits a house and weakens that house for 1-2 minutes then that house will be easier to destroy and lift into the air. The Bowdle wedge was moving very slow so it could sit over an object and just do continues damage to that object the entire time it was over that object. The Yazoo tornado was only over objects for a matter of seconds so it did not have time to sit there and beat a house down. Also it is hard to tell by trees how strong a tornado is. A EF3 tornado can knock down trees just like an EF5 tornado.

The Yazoo tornado was on the ground for alot longer than the Bowdle tornado and for the area it occured in it was impressive. I think the Yazoo tornado could have been an EF5. The Bowdle wedge looks more impressive but I won't base my vote off of images. The Yazoo tornado was hard to see so there is not going to be as many good pictures of it. I think Shane makes very good points. We will never know for sure which tornado was stronger than the other one because of the slower vs faster argument.