Connecting Funnels/Tornadoes

[Andrew Khan]

How can two vortex'/funnels/tornadoes connect with another tornado/Funnel/Vortex, and look like a 'bowtie' or a 'loop' in the sky, here is the picture...

How is this possible? It would seem physics would have to completely crazy to render this, what would make this happen? Here is a video of it happening...



http://www.stormstock.com/SSRARE%7e1.ASF

 

[HAltschule]

WOW. Never seen anything like that before :shock:

 

[Andrew Khan]

Yes, I know, it's pretty wild.....I also have reason to believe that it is a pretty rare phenomenon..

 

[Andy Wehrle]

It has been documented several times before, although I can't say it's exactly a common phenomenon.

http://www.stormgasm.com/5-12-04/simon%20p...cs/tornado7.jpg

Perhaps some of you have seen some video of two funnel clouds that are seen at cloud base ... with time, the vortices curl toward each other and seem to "connect" ... what is happening there is a vortex that wraps around itself, just like a smoke ring. Since air is a fluid, it obeys the laws of fluid dynamics, which include this "law" of vortices (that they either form loops or they end only on a solid surface). NSSL has a photo showing this phenomenon of a vortex ring (see photo #3 in the NSEA Photo Gallery). These have been given the name "bowtie funnels" by some storm chasers.

http://www.cimms.ou.edu/%7edoswell/a_torna...o/atornado.html

 

[Andrew Khan]

That's a good picture. Although, I still am not sure how it happens. Does anyone here, have proof of seeing this?

 

[Morgan Palmer]

All I can think is that there's some kind of developing primary and larger vortex and the other fingerlings are drawn in somehow. Though if that were true, some of them would eventually have to produce condensation funnels.

hmm

 

[Andrew Khan]

It could be associate with a strong large scale rotation, which produces mulitple funnels....but still...I do not understand how they can connect...

 

[Andrew Khan]

Some thought that it could even be mulit vortex tornadoes...

 

[Andrew Khan]

I was just talking with Kurt Hulst, and he had a pretty good theory about what might happen. He said it could be one MAIN funnel/vortex, and a satellite vortex comes out from that one, and goees baack up to the cloud base or around, but looks as though it is connected to it. I thought, it was a pretty good idea.

 

[Mike Hollingshead]

The video the one of the tornado video classic tapes shot in NE has always made me go, hummmmmm. They are identical and come together right over this couple in their backyard.

 

[Shane Adams]

Some chasers (including us) saw one of these just north of highway 160 in south Kansas on May 12, 2004, west of Attica. I've always assumed this was some type of reversal of the pattern that creates mesocyclones, but on a smaller scale.

 

[Dave Kaplow]

Why couldn't this be a single U-shaped vortex hanging beneath the cloudbase? The middle part between the funnels is the lowest, so maybe they're connected from the beginning but at first there's no condensation in the lower middle portion of the vortex. As the vortex intensifies, the condensation fills in, and the funnels appear to join up. Not suggesting this is necessarily what's going on, but it seems one possibility.

Alternatively, if you have 2 funnels hanging next to each other, and one is cyclonic and the other is anticyclonic, wouldn't the natural tendency be for the funnels to merge at their ends? I don't know enough about vortex dynamics to know if this is true or not, but I have a vague memory of reading somewhere precisely this explanation for the merging funnels.

 

[Mike Kay]

Originally posted by Mike Hollingshead
The video the one of the tornado video classic tapes shot in NE has always made me go, hummmmmm. They are identical and come together right over this couple in their backyard.

I remember that. I have one of those Tornado Video Classics tapes at home showing that scene in NE with the unusual connecting U-funnel with the tornado siren blaring away in the background. Pretty darn weird to see.

I've heard of those before I even had those videos, They're sometimes called bowtie funnels.

 

[Roger Edwards]

The Nebraska event you're discussing was 12 Jun 94 over Norfolk. John Hart and I observed that storm for over 6 hours, including the infamous connecting-funnel vortex over Norfolk that appeared on one of the TVC tapes. Our view was from about 1.5 miles to its SSE, whereas the Norfolk resident saw it almost directly overhead. This was one vortex with condensation extending in a U (or, for college football fans, a Miami Hurricanes logo) from the ambient cloud base. Since the vortex axis was bent 180 degrees along a vertical plane, one end was cyclonic, the other anticyclonic.

My slides of that middle/mature stage near OFK didn't turn out well at all, but here is how that supercell looked about two hours later in fading daylight...
http://www.stormeyes.org/tornado/SkyPix/westptne.htm

That was taken near West Point, about 5 hours after the storm's 3:30 p.m. initiation in Antelope County.

We had driven from KC and were at the old Norfolk WSO, analyzing surface charts, convinced we were in the right general area, when the storm blew up to the W. We stayed with it -- at a slow, leisurely pace and on great roads -- for the next 6 hours. Our last view was of the slowly rising and shrinking stack-of-plates, silhouetted by lightning that pierced total darkness N of Tekamah.

The storm was not tornadic, but that doesn't matter. It still ranks among my top 3 or 4 favorite intercepts of all time for combination of absolutely nailing the morning forecast, the remarkable longevity and sustained beauty of the storm, and almost laughable ease of observational strategy. That's a very rare combination!

 

[Mike Hollingshead]

Roger, do you recall if this storm was a prolific anvil crawler producer? I remember a storm in that direction around that time frame viewed from Blair. It was far enough away we couldn't really see much of it but what we were seeing was some super long crawlers flying overhead. I remember that and the very strong southerly winds. Interesting, I am wondering if this was that storm.