Tornado or Funnel?

[Ethan Schisler]

I'm stuck on whether this funnel cloud appears to be on the ground as a tornado. I shot this on October 9th outside Cedar Rapids Iowa. There was a velocity couplet before this storm formed a funnel cloud that appeared high based but upon editing there appears to be some spin up underneath it. Was looking for other opinions. Thanks!

Edit: I do not have video from this partiicular vantage point, I was shooting photos as it caught me off guard somewhat.

 

[Tyler Burton]

I'm stuck on whether this funnel cloud appears to be on the ground as a tornado. I shot this on October 9th outside Cedar Rapids Iowa. There was a velocity couplet before this storm formed a funnel cloud that appeared high based but upon editing there appears to be some spin up underneath it. Was looking for other opinions. Thanks!

Edit: I do not have video from this partiicular vantage point, I was shooting photos as it caught me off guard somewhat.

Hi, Ethan. I’m pretty sure that at the moment that photo was taken, you’re looking at a funnel cloud. I don’t see any dirt or debris getting kicked up at the bottom, plus do you see how the funnel has those scud clouds hanging off of it, and how the clouds around it are just kinda loose and not very compact? Well, that might be sign that the updraft is going through a rough time. So no debris at the bottom combined with the looks of the updraft base makes me think that it’s just a funnel cloud.

 

[Devin Pitts]

I've seen tornadoes with smaller funnels personally, but without being up close enough to observe any potential ground circulation as is the case with that image, I would just go with funnel.

 

[Spencer Dant]

Generally speaking, we're the ones defining whether something is a tornado or funnel - nature doesn't really care about the distinction - so it's not a tornado unless someone has clear evidence that it was a tornado. If there was no survey and you can't actually pinpoint a ground circulation, I would use caution calling it a tornado.

As for whether or not I think that that was ever on the ground (very subjective viewpoint here), more often than not in my experience a funnel extending downward out of the cloud base likely stirred up something on the ground, even if for just a moment. There is no scientific basis for that thought, though.

 

[Ethan Schisler]

Thanks guys. Was just going through my photos and noticed this odd one and figured I would get a second opinion

@Dan Robinson do you have any opinion on this?

 

[Jeff Duda]

If that's all you have for evidence then there is no way to claim with anything more than low certainty that the feature was a tornado.

 

[Ethan Schisler]

I definitely agree. I was just looking for others opinion. I think it was just a funnel, but I thought it would be a good discussion. Excuse my grammar. I broke my arm this week and its my right hand, so I am having a hard time typing.

I appreciate everyone's input on this.

For the record, I wasn't claiming this as a tornado. Just questioning its validity as a tornado vs being a funnel.

 

[Dan Robinson]

I think this most likely had something capable of damage on the ground underneath. Right now the NWS wouldn't count it as they are still in the "funnel to ground or some visual of debris" requirement. I think the recent paper about tornadoes developing ground-up might put a rest to any speculation about these in the future.

 

[Warren Faidley]

I think the recent paper about tornadoes developing ground-up might put a rest to any speculation about these in the future.

Well that doubles my tornado count!

 

[rdale]

I think the recent paper about tornadoes developing ground-up might put a rest to any speculation about these in the future.

Don't overinterpret that The paper is not saying that all tornadoes form from the ground. That's pretty obvious from cases where funnels are aloft and never cause damage at the surface.

 

[Alex Elmore]

I think the recent paper about tornadoes developing ground-up might put a rest to any speculation about these in the future.

I've seen this work presented a couple times now. I think that all tornadoes forming in this manner is possible, especially if observations support it. However, as a scientist, it irks me somewhat to hear see the authors' conclusion that all tornadoes form this way based on a handful of observations when roughly 1,000 tornadoes occur every year. I'm not saying the work is flawed or the results are impossible. There just needs to be more tests and/or observations to make sure that is 100% the case before saying so.

Supercell and tornado simulations are providing some great data on what goes on during tornadogenesis. These simulations show that there are numerous vortices that form along various boundaries (RFD and FFD) under the supercell that get drawn toward the meso. It's when the low-level meso can stretch one of these vortices enough do you get a tornado. So yes, the example provided by the OP could have a circulation on the ground, but possibly the vortex was not stretched enough to become visually tornadic. However, by the AMS definition of a tornado, that would mean this example could be a tornado.

The NWS needs ground truth (pun intended) that a tornado did occur. This is done by observing visual damage or through photographic evidence of ground circulation. So if OP's example is tornadic based on the AMS definition, but there was no evidence of a ground circulation whatsoever, most likely because the circulation was too weak, then no, the NWS is not going to count it. This is why there has been unofficial talk recently on what actually constitutes a tornadic circulation. The atmosphere underneath a supercell is extremely chaotic and has numerous eddies and vortices. The science needs to be vetted before every funnel cloud and weak circulation is considered a tornadic circulation.

 

[rdale]

...and to add on, they aren't saying that you can't have funnels aloft because tornadoes form on the ground first. Just that those tornadoes formed near the surface. In either event, the circulation exists aloft long before the tornado starts, and the public couldn't care less - if there is damage on the ground it's a tornado, if not it wasn't.

 

[Ethan Schisler]

Thank you, Alex. You're comment was extremely informative. I'll be interested to see where this study goes and any future work on it.

 

[JamesCaruso]

So yes, the example provided by the OP could have a circulation on the ground, but possibly the vortex was not stretched enough to become visually tornadic..

Alex your commentary was very interesting but I am having trouble understanding the part that I excerpted above: I certainly understand that there is not always visible condensation, but if there is circulation on the ground, the tornado formed on the ground first (per the subject of your commentary) AND there is a funnel above, then how could it be that “the vortex was not stretched enough”? Wouldn’t having a circulation both on the ground and up above indicate that it was indeed stretched enough, and it’s simply lacking condensation all the way between cloud and ground?

 

[Alex Elmore]

Alex your commentary was very interesting but I am having trouble understanding the part that I excerpted above: I certainly understand that there is not always visible condensation, but if there is circulation on the ground, the tornado formed on the ground first (per the subject of your commentary) AND there is a funnel above, then how could it be that “the vortex was not stretched enough”? Wouldn’t having a circulation both on the ground and up above indicate that it was indeed stretched enough, and it’s simply lacking condensation all the way between cloud and ground?

You're right, but I also said "... stretched enough to become visually tornadic", i.e., complete condensation funnel and/or debris or dirt being vigorously lofted at the surface that provides visual truth that the circulation does exist. There are other reasons as to why a vortex may not be visually tornadic, and this is just one of them. I'm also bouncing between the official AMS definition of a tornado and what the NWS considers a tornado. This is not to say there is a disagreement between the two sources, it's just that the NWS needs visual proof of a ground circulation. This could change if the previously mentioned research and additional studies eventually come to find that if there is evidence of a vortex at the cloud base (e.g., a funnel cloud), then there is a circulation extending to the surface.