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All About Lightning

The state of Florida is famous for its sunshine, beaches, and summertime fun. However, as Floridians, we know that summer also means thunderstorms, and thunder doesn’t happen without lightning. 

In this episode, we will explore the basic science of lightning and thunder, and how you can keep yourself safe this summer. We hope this brief introduction to thunderstorms in Florida will help you feel more informed and prepared for our summer rainy season.

Episode Transcript:

(THUNDERSTORM SOUNDS)

SHANNON:
On today's episode, you'll learn all about lightning science and the safety that you need to consider during thunderstorms in Florida.

(THUNDERSTORM SOUNDS)

LARA:
Welcome to “Naturally Florida,” a podcast about Florida's natural areas and the wild things that live here. I'm Lara Milligan.

SHANNON:
And I'm Shannon Carnevale.

LARA:
This podcast is brought to you by UF IFAS Extension in Polk and Pinellas Counties.

(THUNDERSTORM SOUNDS)

We have been having some crazy afternoon thunderstorms over here in Pinellas County. Shannon, have you guys been having the same thing?

SHANNON:
We have. A lot of them I've noticed aren't actually resulting in rain right where I live, but it surrounds our area and I can see the lightning happening in all these neighboring communities. But I haven't had a ton of thunderstorms right over our property yet.

LARA:
Well I guess that's good and bad. I know you need the rain for your garden, but…

SHANNON:
Yeah.

LARA:
Yeah. Ours has been crazy and the lightning's been crazy. And so for today's episode, we wanted to kind of give you guys some, like, basic lightning science and just some basics behind how thunderstorms happen. And we're gonna start off by talking about clouds. We're going to walk you through the whole process.

SHANNON:
That sounds great because the clouds are honestly part of the best part of thunderstorms, in my opinion. I mean, I love the sound of a good thunderstorm when I'm sittin’ in my patio, but I really love the clouds that we get all day that lead up to those afternoon thunderstorms. So let's jump right on in and talk about why clouds are so important to the thunderstorms that we want to talk about today.

LARA:
What you guys want to look for is the big puffy clouds, the ones that we all drew when we are kids. Those are called “cumulus clouds." And basically under the right conditions, those clouds that were once kind of separated can come together. And then when we get our sea breezes, especially in the afternoons, those clouds will then start to basically have an updraft and they'll start to grow taller and taller and taller.

And I'm sure that's kind of what you were referring to, Shannon, just watching those clouds shift and change.

SHANNON:
Yeah, I love watching those thunderheads build over time. And to any of our listeners who are either new to Florida or maybe don't live here, because our topography is so slight here in the state, you can see these thunder clouds building so many miles away. And it really can be quite beautiful.

LARA:
Yes. And once they kind of build to what we're describing here, we call this “cumulonimbus clouds”—if you want to have your fancy words of the day. The updraft of air that basically forces that column or clouds to rise and that upward movement has to do a lot with, well, A. Florida being hot, but B. us also being surrounded by water.

So we know that land heats up faster than water and warm air rises. Right—I’m sure hopefully many of you have heard that. If not, now you know.

(LAUGHTER)

SHANNON:
If you didn't know, now you do.

LARA:
Now you do. It's less dense than cooler air. So as our land, especially in summer, gets hotter and hotter throughout the day, hot air is created and that air rises. And when that air rises, it basically creates a little like vacuum. There's this empty space now below that's then filled in with the cooler air from our surrounding bodies of water, oceans.

In my case, we're a little peninsula, so we have water everywhere. But that basically creates what we know as our sea breeze and creates ideal conditions for these afternoon thunderstorms.

SHANNON:
Yeah. And that sea breeze, because I'm in the middle of the state, we actually get thunderstorms from different sides of the state depending on the season. And because I'm now on the spot, I'm not going to remember which direction they come from. But right now it seems like most of the thunderstorms that make it over to us in Polk County are coming from the east coast, and other times of the year they come from the west coast. And it's really interesting to watch that happen.

LARA:
Yes. So if you guys see these dark… Well, but they wouldn't start off dark. White fluffy clouds kind of come together, grow vertically and then turn dark. That's like a storm is about to happen.

SHANNON:
It's coming.

LARA:
It's coming. There's some other things that you can kind of look for, which is if you see a big shift in wind, the dark clouds, and sometimes there's also a little bit of a temperature drop, too. If you're like, “Oh, it just feels like it got cooler…” All those three things—you are about to experience a thunderstorm.

SHANNON:
Yeah. And those are, those three signs are something that's very important to keep an eye out for. If you're out camping or hiking or if you're out on the water in a boat, you notice that change in wind, that drop in temperature, you look up, you see a big fluffy cloud that's starting to turn dark. It is time to head inside.

LARA:
Yes. And we're going to talk about some additional tips, kind of like our little call to action at the end. Now, kind of what we want to get into is the science of what's happening within the clouds, which this science is honestly still unknown.  Like this electromagnification that's happening in the clouds, scientists still don't really have clear answers on how it all happens. But generally there's agreement on what I'm gonna attempt to explain to you guys.

SHANNON:
But just take a little bit of that mystery along with it and understand that science is always developing. Right?

LARA:
Okay. Yes. And so I'm gonna attempt to explain this whole process for you, starting with the cloud formation in which clouds are just visible particles of water. And clouds are made up of different sized particles—heavier ones fall to the bottom, lighter ones at the top. When we get the updraft of the sea breeze, those particles shift. And that shift causes basically these electric fields to start. Positively charged particles tend to go towards the top of the cloud, negative towards the bottom.

In general, the earth is also negatively charged, but underneath the thunderstorm, those two negative charges kind of resist each other. And so the earth actually becomes positively charged underneath a thunderstorm, and that creates a negative and a positive charge. And in that case, opposites attract. And that basically is what is responsible for lightning starting, is those opposites create this crazy electromagnetic field and we get lightning.

Okay, that was like…(LAUGHTER)

SHANNON:
That was a lot. No, I think it made sense. So you've got those negative charges going on in the cloud. You've got the positive charge on the earth, and those two attract each other. In this case, that attraction, when it boils over, it becomes lightning. Am I right?

LARA:
Yes. But believe it or not, what we see is actually the light is emitted from the ground to the cloud. But it happens so quickly that to us it looks like it's coming from the cloud to the ground.

SHANNON:
Yeah. And that type of lightning is the one that we are all familiar with. And if anyone has been around Florida for a long time, you'll know that we are often, in the center of the state, referred to as the “lightning capital of the world.” I mean, that's why Tampa Bay's hockey team is the Lightning, because there's so much lightning in this area and it is a formidable foe.

So over the year, the highest frequency of cloud to ground lightning in Florida is actually between Tampa and Orlando. And it's due to the fact that we have so much moisture in the atmosphere, which you and I all relate to, because it's the humidity of summer. There's just so much of it in the atmosphere close to the ground. And when you combine that with the temperatures and the sea breezes, it's a recipe for lightning.

LARA:
It's the perfect storm!  (LAUGHTER) I've been waiting to say that one.  No, I'm just kidding. So. Okay. And so one thing I also want to address, like I remember having these debates as a child, which is, you know, what happens first is it thunder or is it lightning? Can you have one without the other? And so I just want to like, let's all get on the same page here.
SHANNON:
And— let me guess—that argument had to do with whether or not you were allowed in the pool?

LARA:
Probably.  (LAUGHTER)

SHANNON:
Yeah.

LARA:
Summer camp, so probably…

SHANNON:
(LAUGHTER) Same.
 
LARA:
So just to be clear, it is not possible to have thunder without lightning. Lightning is what causes thunder. So therefore lightning happens first, followed by thunder. Now it's possible that you might see lightning and not hear thunder. And that does not mean you win your argument. (LAUGHTER) It just means that the thunder was probably too far away.

We can pretty much only hear thunder about ten miles away. So unless you have really good hearing, but… And that's what people refer to as “heat lightning.” I'm sure you've heard people talk about that. So and that typically happens most often in summer, again when we're having all of our thunderstorms anyway.

SHANNON:
It's really obvious when it's after dark. We call those “lightning shows,” you know. But it's one of the many joys of Florida summer is sitting on your back porch and enjoying the heat and humidity. Maybe you're inside a sunroom or something with air conditioning. But just watching that heat lightning, because, again, we have such low topography, you can see that lightning so far away. 

But when we think about lightning and how dangerous it is, we really do associate it with the sound of thunder. And that's why we hear all the time when it roars, go indoors. So that begs the question, if you can see lightning but you can't hear thunder, is it still dangerous?

LARA:
Yeah. So it is a really good question. In general, we tend to, most of the rules revolve around thunder and being able to hear thunder and not necessarily like when you said you could watch the lightning storms and things like that. If you're not hearing thunder, I wouldn't be as concerned. But definitely if you're seeing lightning and you're outside somewhere, it's probably a good idea to at least like check out the radar and see what's going on.

SHANNON:
Definitely get to a safe space if you can't get access to that sort of information, and know we're talking about probabilities here. So even though the risk might be very, very, very low that anyone could get struck by lightning if you can't hear thunder, the risk does exist. But it's just a lot more dangerous if you're close enough to hear the thunder. Did I say that, right?

LARA:
Yes. And I know, like Shannon and I both, we’re native Floridians. We both did sports as kids, and so we're very familiar. If you grew up doing that, you know, the lightning sirens at the soccer fields and everyone knows how to count to five and do the math for how far away is the lightning. So, but if you're new to Florida or like haven't heard about this, we're going to give you some inside knowledge.

So basically light travels faster than sound. It takes thunder about 5 seconds to travel one mile. And so basically once you see a flash of lightning, you then can start to count “one, two, three, four, five.” Once you get to “five,” and if you heard thunder, that means it's one mile away. And then you can keep going.

If you made it to 15, then you divide by five. That means the strike was three miles away. Now you don't want to be standing out in a storm counting to figure this out. But it is a cool thing that you can do if you're in a safe location to determine how far away the storm is.

SHANNON:
That's really interesting that you divide by five. We were always told “Count your Mississippi’s.”

LARA:
Oh, really?

SHANNON:
Each second was a mile. So that's not good. (LAUGHTER) We were doing it wrong.

LARA:
Depending how quickly you can say “Mississippi,” the math might equal out, but…

SHANNON:
(LAUGHTER) Maybe, maybe. And if you have a big group of kids and they're trying to get back outside, their “Mississippi’s" are pretty dang quick.

LARA:
Yeah that’s true. 

SHANNON:
(LAUGHTER) Anyhow, anyway…

LARA:
Yeah. So in general, again, I was kind of corresponding back and forth with our lightning research group at UF.  And they said that you should move to a reasonably safe shelter when you see dark clouds or hear distant thunder is their general recommendation. 

Now, Shannon and I want to clarify what we mean by “safe shelter.” So that means an enclosed building, or if you are in a vehicle like a hardtop—not a convertible—hardtop vehicle. The things like carports, like I always remember as a kid, you just like hide under a picnic shelter. Or like…

SHANNON:
We literally ran to a giant metal pavilion. Looking back on it, it’s probably the worst place we could have gone was a large metal pavilion, but it was because we were surrounded by fields on all sides and we were usually there after the gymnasium had closed. There was nowhere to go.

LARA:
Exactly. So clarifying (LAUGHTER)—now that we are more informed—things like carports, open garages, any type of open shelter like that are not considered adequate shelter in a thunderstorm. You also want to avoid higher ground or isolated trees. So trees just tend to give off more of that positive charge. It's closer to the clouds. So it just creates a greater, I guess, venue for lightning to occur. So don't seek shelter under a tree.

SHANNON:
And another location you need to avoid that is very relevant to our Florida audience is get off the water. And like do not be out boating, trying to outrun the storm. If you think the storms are coming, get home first.

LARA:
Yeah, there's a lot that you need to be aware of as a Floridian or if you're visiting—especially in summer if you're not familiar with how everything works—‘cause it can happen really, really quickly. So I'm always checking the radar. Always.

SHANNON:
Yeah. And I have like I said, I've got multiple apps because I don't trust just one. (LAUGHTER) So I have two or three different apps, and I've got them set to follow my location and give me a lightning alert if it's within, I think, 15 miles. Even though I think you said earlier 10 miles is a good rule of thumb there, just because it gives me a little heads up that it's happening. And on days that I'm taking groups of people for work, like taking people out hiking, I set it to 20 miles. Because I want to know ahead of time that we have a storm coming and we need to get to somewhere safe.

LARA:
Yes. Yeah. And I do want to also specify… And maybe you said specifically the beach, Shannon.  Did I miss that?

SHANNON:
I said just water. Like I said, if you're out fishing or something, especially if you're offshore. But on our lakes, you're really… You know, in the center of the state, you're not more than a couple of minutes from shore.

LARA:
Right. So yeah, that includes the beach. If you're like, “Oh, I'm not in the ocean,” you need to get off the beach, too.

SHANNON:
Yeah.

LARA:
Yeah. And don't be holding anything metal. So, believe it or not, like I was looking at statistics and between 2006 and 2009, the majority of lightning deaths occurred while people were fishing. So they're holding…

SHANNON:
Really?

LARA: 
Yeah.

SHANNON:
Wow, holding a little miniature antenna.

SHANNON:
We always thought about that with our lacrosse sticks, I will say.

LARA:
Mm hmm. I'm sure that's not too much different. (LAUGHTER)

SHANNON:
Putting our lacrosse sticks down in our open pavilion probably made us super safe, but…

LARA:
Extra safe

SHANNON:
Yeah, but you live, you learn. And now we know.

LARA:
Yes.

SHANNON:
So we've all been in those scenarios where you just can't get to a safe shelter, right, Lara?

LARA:
Oh, yeah.

SHANNON:
Yeah. So you need to have a contingency plan before you go out. Any time you are going out into wild spaces in Florida, anywhere where you might be more than 10 minutes from a vehicle or a safe building, you need to have a contingency plan. You need to know what you're going to do, especially in the summer, because it's really not an “if” the storm comes, but a “when” the storm comes.

So when you're planning your outdoor activities, definitely make a lightning plan. It is the responsible thing to do. And I would say in the summertime you are more likely than not to need your lightning plan. But if you find yourself somewhere where you absolutely cannot get to a safe space or an enclosed building, we do have a couple of recommendations.

These are last resort recommendations. So, I want to emphasize that. So let's say you're out backpacking and you're out in the Kissimmee River Basin and there is not a car for miles around and you see storms coming. When that lightning and thunder come, what you want to do is you want to crouch down, get into a small position, make yourself as small as possible, not under a tree, and just minimize your contact with the ground as much as possible.

You need to be in a position you can maintain, so don't be on your tiptoes the whole time, but minimize that contact with the ground. Cover your ears, keep your head down and try to stay that way for the duration of the storm. And, you know it's Florida. That storm might only be 5 or 10 minutes. There's a chance it'll be longer, but just make yourself as safe as possible. And then remind yourself, “Hey, next time I need a better plan because this is scary and I don't like it.”
LARA:
Yeah. Yes. Now, in the very rare chance that you were ever with somebody that does get struck by lightning, obviously we want to get them medical help immediately. That's, you know, 911. There's no questions asked. And so we'll just leave it at that. There's no delaying. Just call 911. Get help ASAP.

SHANNON:
Yeah, there's really nothing you can do. You need to get emergency medical involved as soon as possible.

LARA:
So just some kind of sayings to maybe help you guys remember some of the things Shannon and I have been saying today… Shannon mentioned this one before, but “When thunder roars, go indoors.” That's the shortest, probably easiest one. It rhymes. So if you don't remember anything else, just remember that.

SHANNON:
Yes, very simple, to the point.

LARA:
Yes.

SHANNON:
Get inside.

LARA:
There's a little bit longer one that has a time included into it. So it says “Half an hour since thunder roars, now it's safe to go outdoors.” So the general rule of thumb is once you hear thunder, that you should wait 30 minutes to ensure it's safe before you go back out.

SHANNON:
Yeah. Which is going to be a total bummer to the kids wanting to get in the pool.

LARA:
Oh, gosh, yes. If you're with youth, it's like just “I'm sorry.”

SHANNON:
Yeah, there's going to be some very upset little kiddos on summer break, but we want to keep everyone safe and make sure that they can get in the pool at some point. And so that half an hour number is a good, easy one to remember.

LARA:
Yes. So, yeah, I mean, I hope that you guys, you know, maybe learned something new about clouds or lightning or thunder. And please, just remember, if you're planning to go outside, just check the forecast, get into the habit and routine of that. Check out the radar. If you're doing something outside and you have somebody back home that could kind of be checking on it for you. And just get inside if you hear thunder—somewhere safe.

SHANNON:
Yeah. And we all joke in Florida, you can't plan your life around a 50% chance of rain because that's every day. So we're not saying don't go outside, don't recreate, don't go fishing, don't go swimming. That is not at all our point. Just have a plan. Where is that safe space? And if you get separated from your group for whatever reason, does everybody in the group know where the safe space is. And if you're going somewhere where you're not going to have cell reception and it will be difficult to call 911 in case of a lightning emergency, have a plan for that, too.

LARA:
Okay. And with that, that wraps up our episode today on lightning. And we will include a ton of resources per usual in our show notes, so be sure to check them out.

(THUNDERSTORM SOUNDS)

SHANNON:
Thanks for listening to “Naturally Florida,” a podcast about Florida's natural areas and the wild things that live here. Stay updated on new episodes by subscribing on your favorite podcast platform. If you enjoyed today's episode, consider sharing it with a friend. “Naturally Florida” is produced by your hosts, Shannon Carnevale

LARA:
and Lara Milligan.

SHANNON:
If you have questions or suggestions, submit them online at naturallyfloridapodcast.com. This podcast is brought to you by the University of Florida's Institute of Food and Agricultural Sciences Extension, an Equal Opportunity Institution. Thank you for listening.

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