Did this tornado last 7 hours?

[MatthewCarman]

I heard about a tornado that lasted several hours and started a topic on another site and several chasers were saying because of the date it was unlikely it lasted 7 hours but several sites claim it does and I first heard it lasted 7 hours at the end of storm stories on TWC once if I remember correctly. So what is the proof to back up this tornado lasting 7 hours? Who witnissed it or saw it? Could it have been multiple tornadoes? What are your thoughts?

Taken from a site on google:
Most tornadoes last only a few minutes and have an average [athe length of about 7 kilometers (4 miles). There are cases where they have reportedly traveled for hundreds of kilometers ans have existed for many hours, such as the one that lasted over 7 hours and cut a path 470 kilometers (292 miles) long through portions of Illinois and Indiana on May 16, 1917.

 

[rdale]

Of course it did not last 7 hours. That's not possible.

From NWS ILX:

May 26, 1917
A major tornadic thunderstorm took a 293 mile track across central parts of Illinois and Indiana. Once believed to be a single tornado, later study indicated it was likely at least 8 separate tornadoes. The first touchdown was about 20 miles southeast of Quincy. The tornadic storm tracked due east, before beginning a southeast curve near Charleston. The tornado was on the ground for over 7 hours. The towns of Mattoon and Charleston bore the brunt of the tornado. Damage from this severe tornado in Mattoon was about 2.5 blocks wide and 2.5 miles long, with over 700 houses destroyed, while the Charleston portion was 600 yards wide and 1.5 miles long, with 220 homes damaged. Damage in the two towns amounted to about $2 million, in 1917 dollars. 53 people were killed in Mattoon, and 38 were killed in Charleston. Overall, 101 people in Illinois were killed during the tornado outbreak, with 638 injured.

 

[Josh Richardson]

I think Matthew was referring to me and some other people at another site and we said it was unlikely that it lasted for that long and we would never, of course, know due to it being back in 1917. I'm also fairly certain that someone posted that same paragraph that Mr. Dale just posted but it was a long time ago so I'm not sure. What made you bring this up again all of sudden?

 

[Dustin Fan]

Yes, it would be impossible, no single supercell could keep one tornado on the ground for that long. Thanks Rdale.

 

[Doug Lee]

Back before WWII, before radar and the sophisticated radio networks (amateur and public service) we have today, before the Weather Bureau began issuing tornado warnings, most of the information about tornadoes came from newspaper reports after the fact. Reporters back then probably knew little more than the general public. Even meteorologists didn't know that much back then because very little research had been done at that time. When you combine this general ignorance of how severe storms behave, with a general tendiency to embellish the potential of a single threat, you come up with reports that attibute damage to one storm that was actually done by several.

A single long-lived system can produce several tornadoes, but the paths of the tornadoes will roughly parallel each other. This also contributes to one tornado being credited with staying on ground for so long.

Grazuliis' book, The Tornado: Nature's Ultimate Windstorm explains this in much more detail and in a more articulate way than I have. If you haven't read it, check your local library or see if someone is selling a used copy online.

 

[MatthewCarman]

Josh thanks for adding your thoughts to this thread and I brought it back up because I wanted to see if anyone had any proof the tornado was on the ground for 7 hours and 20 minutes. I realy dont think it was to be honest but I igured if anyone knew the answer it would be someone here.

Rdale thankyou for that article. I realy dont think it would be possible eather because most dont even last 15 minutes so that did seem inpossible. I first saw ths on TWC after a storm stories episode so that is why I thought it was true. This is good discusion anyways.

 

[Gabe Garfield]

Of course it did not last 7 hours. That's not possible.

How do you know it did not last 7 hours? What physical laws dictate that a tornado cannot last that long? I agree that the odds of a tornado lasting that long are very small, but I would not be so bold as to say that it is impossible. A tornado does not know how long it has been on the ground.

A single supercell tracked across 7 states (IIRC) on March 12, 2006. If it had had a tornado on the ground the entire time, it's possible it could have approached the 7 hour mark.

Just because such an event has never been substantiated to have happened does not mean it could not occur.

Gabe

 

[rdale]

The physics of tornados and their formation/demise prevents a 7hr tornado.

 

[Gabe Garfield]

The physics of tornados and their formation/demise prevents a 7hr tornado.

Source?

Gabe

EDIT: I apologize if my tone reads a bit haughty. I was just trying to point out that unlikely scenarios will, on occasion, occur (as long as there isn't a violation of a theoretical upper limit).

 

[Gary Stofer]

When it comes to nature, anything is possible.

 

[rdale]

No, I'd have no doubt saying that a hurricane over the Arctic or a 48 hour continuous supercell is quite clearly IMpossible.

 

[David Drummond]

You know, I remember not all that many years ago that we all thought seeing 6 or 7 tornadoes in one day, let alone one storm, was in fact not possible. It seems to happen several times a year now to many chasers.

While I agree, the possibility of one storm keeping down a single tornado is way out there on the odds, I would never say without a doubt that it is not possible.

 

[rdale]

You know, I remember not all that many years ago that we all thought seeing 6 or 7 tornadoes in one day, let alone one storm, was in fact not possible.

But that's because we thought that one storm could have a 4-7 hour long tornado with it. Then we learned that it was several shorter tornadoes, and we know the science of circulations and cutoff and regeneration and occlusion (at least enough to understand why a tornado doesn't last forever.) So thinking we're missing something that would allow for a 7hr tornado just doesn't seem to fit with the science of the day.

I suppose if you want to force the issue, sure -- it's possible. But that chance is so incredibly small it ranks only in front of the hurricane over Lake Superior ;>

 

[Tony Cook]

Doesn't Dr. Doswell's latest study of the tri-state tornado conclude that it was a single tornado, on the ground for 3.5 hours?

http://www.stormtrack.org/forum/showthread.php?t=11496&highlight=doswell+tri-state

 

[rdale]

They didn't find evidence that it wasn't a single tornado - given the reporting methodology of the time, I'm not sure that is the same as saying it WAS a 3.5 hour tornado. But even if so that's still below the low end of my range ;>