Bill Burton: Lightning Part Two. Last week we tackled negative lightning. And negative lightning just kind of brings you down. Positive lightning just uplifts you. That's the difference, right?
Tawana Andrew: That, and it's a lot scarier, in my opinion.
BB: Well, enlighten us, please.
TA: Oh, I liked your pun there.
BB: I do what I can.
TA: Just absolutely magnificent. So while negative lightning develops from the negative charge at the bottom of the cloud, like we talked about last week, positive lightning shoots from the positively charged cloud tops. So that makes it a little bit more different and a little bit stronger, in fact. So the formation of the actual lightning strike is the same, whether it's positive or negative. The only difference is that this time around, there's a net positive charge transfer between the cloud and the ground. And we don't really see a whole lot of positive lightning strikes. In fact, less than 5% of lightning strikes are positive. However, they are much more dangerous than their negative counterparts, and the reason for this is the fact that they have to travel a lot further to reach the ground, so that electrical field is much stronger. So here's the thing, positive lightning strikes will last longer, and they can have an electrical charge of nearly 10 times greater than a negative strike. So to put that in context, the positive strike can have as much as 300,000 amps. Or, in another way to put this, yeah, a billion volts of energy. That's a billion with a B.
BB: Wait, 1 billion volts?
TA: Yes, like with the pinky up and everything. 1 billion volts.
BB: Wow.
TA: And while negative lightning can travel 10 to 12 miles away from a thunderstorm, positive lightning can strike more than 25 miles away from a storm. So this is why positive lightning, I said it's a little bit scarier. Plus, it's often associated with severe weather, because you have these strong, super cells, these massive cumulonimbus clouds, and these are more likely to have powerful updrafts and a substantial charge separation that could lead to those stronger positive lightning strikes. And since they have such a large amount of energy, they are much more damaging and also much more lethal. So regardless of the lightning's charge, whether it's negative or positive, you got to bring back the famous line when thunder roars, go indoors. It's just better to be safe. It's better to be safe than sorry.
BB: Absolutely. And literally words to live by.
TA: Literally, yes.
BB: And now we have a much better understanding of negative lightning from last week's edition of Science Behind the Forecast, and then the other part of the equation, positive lightning, from this edition of Science Behind the Forecast with WAVE 3 meteorologist Tawana Andrew. Thanks for the knowledge, Tawana.
TA: Of course.
This transcript was edited for clarity.
