Lightning Question...

[Ben_Jacobi]

I'm not really sure if I should be posting this here, so forgive me if that is incorrect. The other day 4/22 a line of thunderstorms came through our area. I was excited since I couldn't chase the storms in the panhandle and was hoping to catch some lightning photography from the line of storms. I got my wish and spent an hour photographing the lightning from my apartment balcony. Some of the lightning was really photogenic and some of it left me a little curious. There were several times when I saw a quick bright flash above my head and see a strike off to the west by a few miles. It was a very short, but intense duration and when I looked at the photos the lightning was a very smooth bolt with no branching. Were these positive strikes I was seeing? I don't really know how to explain it, so I included a photo. I know its not my camera settings because there were other strikes in between with lots of branching. Any idea what might be causing the smooth bolt? Thanks.

-Ben

 

[Todd Rector]

Yes. Positive CG lightning is notable in that it does NOT branch off, instead concentrating in a single, powerful bolt. They have a unique thunder as well - a single BOOM! rather than the crackly sound branched lightning makes.

 

[Michael Snyder]

I'm not really sure if I should be posting this here, so forgive me if that is incorrect. The other day 4/22 a line of thunderstorms came through our area. I was excited since I couldn't chase the storms in the panhandle and was hoping to catch some lightning photography from the line of storms. I got my wish and spent an hour photographing the lightning from my apartment balcony. Some of the lightning was really photogenic and some of it left me a little curious. There were several times when I saw a quick bright flash above my head and see a strike off to the west by a few miles. It was a very short, but intense duration and when I looked at the photos the lightning was a very smooth bolt with no branching. Were these positive strikes I was seeing? I don't really know how to explain it, so I included a photo. I know its not my camera settings because there were other strikes in between with lots of branching. Any idea what might be causing the smooth bolt? Thanks.

-Ben

Im thinking more likely the limitations of the camera that captured the strike and due to distance, the fact that it only is going to catch one split second of the strike is why you only see a smooth stroke. CG strikes have branches all the time, but cameras and your eye may not catch them due to your vantage/timing of the strike.

Dont forget that LTG will also play tricks with your eyes, and that a single stroke can extended large distances IC or CG. Many times you are only seeing part of the strike as it moves through clouds.

 

[Howard Robinson]

Hey Ben, were you trying to catch something like this https://stormtrack.org/media/lightning.504/

 

[SCombs]

Most common (90%) CG strikes are negative strikes. Less common are the positive strikes. The appearance is the same just current flow is different. By the way, positive lightning strikes are believed to be the most dangerous, since they can produce very large currents, up to 300,000 amps! That being said I would agree with Michael Snyder.

Be safe out there.

 

[Mike Marz]

Here is an example of a positive strike that had a nice smooth appearance. This was back in June on an Iowa storm chase with massive cape. This positive CG barrage was incredible and actually had me worried. They were coming down like this every 5-10 seconds and it felt pretty dangerous being where I was. My car was nearly struck by one of these positive bolts not long after this picture.

Here is the video of when my car was nearly struck...

 

[Jeff Duda]

Yes. Positive CG lightning is notable in that it does NOT branch off, instead concentrating in a single, powerful bolt. They have a unique thunder as well - a single BOOM! rather than the crackly sound branched lightning makes.

Is it the case that EVERY CG that does not exhibit branching must necessarily be a +CG?

 

[Dan Robinson]

Generally speaking, yes an unbranched CG is almost always positive. The positive leader propagates differently than the negative (the former in smooth, continuous manner, the latter in more tortuous, discrete, branching steps). That's not to say that every +CG is unbranched, though - some do contain extensive branching, but it tends to be confined to higher altitudes/above cloud base.

It's worth noting that subsequent -CG return strokes are unbranched, so a photo that misses the first branched return stroke of a flash might be incorrectly identified as a +CG.

 

[Mike Marz]

Is it the case that EVERY CG that does not exhibit branching must necessarily be a +CG?

I don't think that is the case, and I definitely think there are some positive CG's that do exhibit some branching, but I also believe it is fairly easy to tell whether or not you are witnessing a positive CG or a negative one. I may be wrong, but I thought that these "bolt's from the blue" https://www.flickr.com/photos/lou1003/17035011486 that Dan posted in a different thread were also examples of positive strikes, and these do have extensive branching. Please correct me if I am wrong and these are thought to be negative strikes.

On second thought... I am guessing those examples of bolts from the blue are probably negative. I would think that a positive CG that is considered a bolt from the blue would originate from the anvil.

 

[NealRasmussen]

That's strange. I thought the + ones flying down from east of the wall cloud where often branched.
They're typically very branched, hairy, and always 1 stroke.

I find it curious that the +CG is thrown around so much. If it's a single hairy branched strike to
the east of a rotating wall, I call it a +CG. Other than those, I have no clue. Just cause visually
there was only one stroke? Like we could tell if there were 2 or 5 within 0.05 sec?

That positives are smooth is news to me for sure. Heck, search google for Positive CG. Seems
like most all are positives. Especially if it struck close.

Perhaps the branching has to do with the how fast the charge built up? Slow buildup and many
leaders find their way down. One makes contact. Whereas if the charge builds up fast... No clue,
really.

 

[Dan Robinson]

With most of those clear-air bolts, the photos are taken from great distances showing an unusually long length of the channel not normally seen with your typical CG emerging below the cloud base.

 

[kevin-palmer]

Have you guys seen this amazing lightning picture from Mike Olbinski showing a negative strike with positive upward leaders: https://www.facebook.com/mikeolbins...73664702357/10153052824777358/?type=1&theater

 

[Dan Robinson]

You all would probably be interested in Dr. Martin Uman's books that go into great detail about these processes. Very fascinating to learn how this stuff happens. I credit his books to getting me into lightning photography and storm chasing.

http://www.amazon.com/All-About-Lightning-Martin-Uman/dp/048625237X

http://www.amazon.com/Martin-Lightning-Dover-Physics-Paperback/dp/B00RWQAI84

 

[Kevin Rimcoski]

Have you guys seen this amazing lightning picture from Mike Olbinski showing a negative strike with positive upward leaders: https://www.facebook.com/mikeolbins...73664702357/10153052824777358/?type=1&theater

Yes. Very rare to get that from what I've been seeing around. And being close...it's a great shot. He's a dam good photographer imo.... I blame him for my newfound photography passion and new addiction to shooting lightning

Sent from my SCH-I545 using Tapatalk

 

[John Farley]

OK, everyone - the video capture below that I got from Rozel may include the most-photographed lightning bolt ever, since lots and lots of folks captured it while observing the Rozel tornado. I have seen pictures of it and the tornado from literally every angle. I have been assuming since that day that this was probably a positive bolt since it was smooth, and as far as I could visually observe in person or see in any of the many pictures I have seen, it had no branching. So am I right in assuming that this was a positive bolt? I figure this is a good example to discuss since so many people saw and documented it.

 

[Mike Marz]

In my opinion, yes, that bolt near the Rozel tornado there is definitely a positive strike.

 

[Dan Robinson]

Yes the Rozel strike was a positive. Most CGs around the mesos/tornadoes of supercells are positives, though there have been some exceptions - the Mulvane and June 12, 2005 Kent County, TX storms for example had mostly negative CG activity in/around the meso.

Another characteristic of the positive CGs is that they usually have only one return stroke. The current pulse is very short, but it is so intense/hot that the channel usually has a longer "bead out" stage. The thunder is also very distinct with positives - it sounds like a cluster of sonic booms.