Rate the tornado..

[Andrea Griffa]

Hi all
I wanna discuss with you for the rating of a strong tornado that occurred in Northern Italy(Guidizzolo) on july 9. I know very well that is better to be on the place to rate a tornado but I will appreciate every attempt to classify by the images of the damage.
I've seen a lot of times those pictures, with the PDF of the EF scale on the hand, and I came to the conclusion that probably we had a EF2. Lemme know what you think.

Here is the image of the tornado and some pictures of the damage.

http://gazzettadimantova.repubblica.it/multimedia/home/797645/1

Here the aerial pics.

http://gazzettadimantova.repubblica.it/multimedia/home/797673


Here other damage pics
http://gazzettadimantova.repubblica.it/multimedia/home/797529

 

[Michael O'Keeffe]

Though I'm not sure how well built the homes in Italy are but at first glance I'd say EF-1.

 

[Andrea Griffa]

Though I'm not sure how well built the homes in Italy are but at first glance I'd say EF-1.

Italian building are not as american ones: the mayor part is built with reinforced concrete.Every wall is made with bricks and iron reinforcing rods.Otherwise we have houses with bricks without iron.So when you rate you have to keep in mind this thing. Personally I ruled out EF1:too much bearing walls collapsed.
Other damage links

http://www.stormtrack.org/forum/attachment.php?attachmentid=626&stc=1&d=1186763803

http://gazzettadimantova.repubblica...o=gazzettadimantova_1337435&idmessaggio=59096

 

[Tony Lyza]

Those attached images you posted would probably scream EF2 in the US, and if the construction is truly as good as you claim, the third may make a case for low-EF3, but EF2 is a pretty solid bet, even off the aerials.

 

[Evan Stubbart]

Hard to tell

It's hard to tell. Some of the pics don't make it look that bad while others do. I'm guessing an overall rating of EF2 as most of the damage to structures appears just to be roof tiles, etc (not major building failure, etc).

 

[Andrea Griffa]

It's hard to tell. Some of the pics don't make it look that bad while others do. I'm guessing an overall rating of EF2 as most of the damage to structures appears just to be roof tiles, etc (not major building failure, etc).

That's the same thing I thought about this case: analyzing the intensity of the tornado by the pics, you could see a mayor damaged zone and probably that zone is the one where you can see the stronger damage of the attached pictures. But you can't rate a tornado as EF3 onle because you see two bearing walls of two houses partially collapsed, even if those walls are well built. That's the reason why I'm for rating EF2.

 

[Willie Dines]

Hi Andrea , How are you?

I have taken a look at the damage photos and also the images of the tornado itself, and to me, it looks very much like an EF2, and I'll explain my reasons in a little more details, which I hope will be of some help

Firstly, looking at the various images of the tornado, and also the aerial photo, it looks very much like the acual funnel of the tornado, never made it to the ground, but instead the damage was cause by weaker rotation underneath the funnel, no had the main funnel made it all the way to the ground, I feel that the damage would've been much worse, but saying that EF2 damage is still nothing to sneeze at

Alot of the damage looks to be to roof tops and higher more higher level sctructures, and also, there's no signs of any ground level damage, like overturned cars, that are a characterist of even EF2 - EF3 tornadoes, and so, this also gives me a reason to believe that the ground level rotation, was weaker, than the funnel's rotation because the funnel was close to the ground, but judt didn't make it all the way down, but still powerful enough to cause a fair amount of damage

Like it has been mentioned before, it is hard to rate tornadoes by looking at imagery alone, but with the many various pics of damage that are available, it was the aerial images that game me most of the informatin about the tornado's path, and tornado images, they are a very good start, and I think that you done a great job in presenting whatever information that you could find

And so, with this in mind,I think that your thoughts on an EF2 rating are bang on target

I hope that this is of some help or another, and perhaps there are a few others that may be able to elaborate on what I have mentioned, either way

Willie

 

[Glenn Rivers]

Tornado Rating

My take on this is just a bit different. To me this was a full tornado, not a "funnel cloud" . So what if the condensation funnel did not reach the ground.....if the relative humidity had been a bit higher, the visible funnel would have been wider and would have reached all the way to the ground.

The damage to me (and I am not an export) looks like a lot of EF 0 and EF 1 damage, with a little EF 2 damage. Tornadoes are rated by the worst damage that they do, not by all the weaker damage they cause, so that would make this a EF 2 tornado based on the damage to the one or two houses that got the worst of it.

Remember, even an EF 5 tornado can do EF 0 damage to shingles and dog houses along the edge of its path.

 

[Doug Lee]

Remember that a tornado does not have to have a single rating over its entire path. I remember the map of the May 3.1999 tornadoes showed some starting at, say, an F-3, and then go through a stretch as an F-4, before weakening to an F-3 and maybe an F-2 before dissipating.

So, what may have happened in this case, the tornado was mostly an EF-2 with a short peak of EF-3 damage. But it really depends on the details.

 

[Andrea Griffa]

Remember that a tornado does not have to have a single rating over its entire path. I remember the map of the May 3.1999 tornadoes showed some starting at, say, an F-3, and then go through a stretch as an F-4, before weakening to an F-3 and maybe an F-2 before dissipating.

So, what may have happened in this case, the tornado was mostly an EF-2 with a short peak of EF-3 damage. But it really depends on the details.

Yes guys I know well that a tornado does not have to have a single rating over its entire path: I've got some experience about;my arguement was that you can't rate a part of the tornado path EF3 only because you see only two walls collapsed and the rest of damage is more close to EF2.I make you an example: are you sure that bearing walls were not hit by a metal tower fall down?
Then it's obvious that at the first stage or in a medium stage the tornado could produce only F0 or F1 damage.

 

[Tony Lyza]

Yes guys I know well that a tornado does not have to have a single rating over its entire path: I've got some experience about;my arguement was that you can't rate a part of the tornado path EF3 only because you see only two walls collapsed and the rest of damage is more close to EF2.I make you an example: are you sure that bearing walls were not hit by a metal tower fall down?
Then it's obvious that at the first stage or in a medium stage the tornado could produce only F0 or F1 damage.

Well, actually, you can, but you do have to have an understanding of the quality of construction and any outside factors that may have led to the more severe damage. But F3 ratings have been awarded for single building destruction. The best example I can give is Stratford, IA, on November 12th, 2005, when the tornado was upgraded to F3 based on the destruction of one house in the path, even though all the surrounding houses signified F2 damage. The point is, if there is an instance of EF3 or F3 damage in the path that cannot be explained by faulty construction or a special outside force, then I believe that EF3/F3 would be applied.

 

[Andrea Griffa]

Well, actually, you can, but you do have to have an understanding of the quality of construction and any outside factors that may have led to the more severe damage. But F3 ratings have been awarded for single building destruction. The best example I can give is Stratford, IA, on November 12th, 2005, when the tornado was upgraded to F3 based on the destruction of one house in the path, even though all the surrounding houses signified F2 damage. The point is, if there is an instance of EF3 or F3 damage in the path that cannot be explained by faulty construction or a special outside force, then I believe that EF3/F3 would be applied.

Obviously you hve to be in the place to make some similar accurate considerations about limited damage in a so little area of damaged buildings. Anyway,Tony, I don't know the Stratford, IA case but if they rated the tornado as EF3 only watching a very limited damage area probably there was a specific reason,maybe after have seen all the objects and type of buildings present in the entire area and after some calculation. Actually it seems to me that damage could be caused by the fall of a near jib fallen down.