The long-established funnel VS tornado paradigm: flawed?

[rdale]

I'm not sure you need a "scientific study" to use the criteria in effect now. Before we knew about tornadoes, any funnel with a cloud that didn't touch the ground was a funnel. Then as we learned, we realized the winds can touch the ground even if the cloud didn't, so many offices "relaxed" the reporting criteria.

But I know of no office that relaxes it when the data goes to NCDC. If there's no damage on the ground - it isn't a tornado. Doesn't matter if the funnel was 1/3rd of the way or 90% of the way -- the scientific definition of tornado and the EF0 lower limit requires ground truth.

 

[calvinkaskey]

Do you have video of this picture?

Here's an obvious example of not a tornado. This feature was rotating under a classic supercell, and developed right where a tornado should, and it condensed most of the way to the ground. Some chasers (most at a distance of a few miles) reported this as a funnel. It was, however, rotating at the speed akin to a roll cloud than a tornadic funnel. Definitely too weak to be a tornadic funnel cloud, but it is rotating and it might have a weak surface based circulation. There's a big grey area between these examples.[/QUOTE]

 

[Skip Talbot]

Do you have video of this picture?

At 8:40 in the following video:
http://youtu.be/qNwA3ipryXY?t=8m40s

Watch video >

 

[Mark Ellinwood]

The, the eternal problem of humans trying to make everything defined to fit into neat little boxes, when nature's lines are always grayed.

There will be no definition that makes everyone happy. Personally, I like the "you must prove that there is a circulation on the ground" approach, whether it be from a condensation funnel, dirt and debris getting kicked up, or seeing the damage pattern in the aftermath. It's the only way to know 100% for sure (or close to 100%) that the circulation in fact reached the ground. I have no desire to count maybenadoes, both for personal record and for the official record.

 

[Michael Gavan]

The, the eternal problem of humans trying to make everything defined to fit into neat little boxes, when nature's lines are always grayed.

Well said.

I think if you have tornado damage, It's a tornado. If you have video proof of a ground circulation, it's a tornado. If you have a tornado cyclone under a rotating wall cloud, it's a tornado. The problem with the last one is that it doesn't matter. It's like a rain drop that never fell (Virga) never gets measured. The radar can see it, but in the end it didn't nothing on the surface---Doesn't mean it didn't happen, it just didn't matter.

 

[Adam Lucio]

They very definition of a tornado includes contact with the ground. As with rain, rainFALL is measured, not the raindrops themselves that makeup the rainfall. Unless I know for sure there was ground contact, its a funnel cloud. I try to keep things simple.

 

[calvinkaskey]

It's kind of hard not to think this isn't touching the ground though isn't it?

 

[calvinkaskey]

Tt should matter because the only way to get a fair risk assesment is to look at tree damage and tornadoes that don't hit any structure.

I think if you have tornado damage, It's a tornado. If you have video proof of a ground circulation, it's a tornado. If you have a tornado cyclone under a rotating wall cloud, it's a tornado. The problem with the last one is that it doesn't matter. It's like a rain drop that never fell (Virga) never gets measured. The radar can see it, but in the end it didn't nothing on the surface---Doesn't mean it didn't happen, it just didn't matter.

 

[Marcus Diaz]

View attachment 8795 It's kind of hard not to think this isn't touching the ground though isn't it?

That depends? Was it rotating? I've seen several areas near the FFD that could be mistaken for funnels or tornadoes because of their shape (I have a few examples of this). I'm willing to bet that storm there is in a high moisture environment. In which case there's a lot of times the inflow tail can develop nearly scraping the ground.

 

[Rick Schmidt]

View attachment 8795 It's kind of hard not to think this isn't touching the ground though isn't it?

If that cloud feature is behind the hill in the background, it could be a couple hundred feet above the ground.

 

[calvinkaskey]

It was definately tornadic, strong short lived. Might have only been 30 seconds on the "ground"

 

[JustinPhillips]

Would need to see pics showing a fuller scale, or video, honestly cant tell much by that photo...

 

[calvinkaskey]

Yeah and I didn't just take the best and most comprehensive tornado video along the entire east coast this year. I have enough confidence in you guys to believe you if you said you saw a tornado.

 

[Michael Gavan]

Tt should matter because the only way to get a fair risk assesment is to look at tree damage and tornadoes that don't hit any structure.

I think we are in agreement here. Evidence of a Tornado means Tornado to me. Even if it's tree-top damage. It matters.

 

[ChristofferB]

Here's an obvious example of not a tornado. This feature was rotating under a classic supercell, and developed right where a tornado should, and it condensed most of the way to the ground. Some chasers (most at a distance of a few miles) reported this as a funnel. It was, however, rotating at the speed akin to a roll cloud than a tornadic funnel. Definitely too weak to be a tornadic funnel cloud, but it is rotating and it might have a weak surface based circulation. There's a big grey area between these examples.

Funny when you see a photo and you realize you must have been standing almost next to the person when it was taken. One of my favorite photos (I've taken myself) was of that funnel/roll cloud. I had it as a background photo on my credit card for a while even.

This was taken about 1-2 minutes before your photo (I have a very similar photo like yours as well). We were standing quite near and really hoping for it to touch down since it would have been absolutely beautiful, but it never did. Our visibility of it was very good so I'm quite sure.