Woman Records Rare, Dangerous ‘Positive Lightning’ Strike on Video

Once, when I lived in Louisville, KY, I witnessed a lightning strike that hit the ground a few dozen feet from my vehicle, as I was merging on to the Gene Snyder Expressway. If you’ve never been close to a lightning strike, it can be difficult to describe the experience. At that range, there’s no perceivable gap between the lightning and the thunder. I was momentarily blinded (while driving at speed) and felt the thunder as a physical shockwave through the air as much as an audible phenomenon.

I was, in a word, shaken. The only reason I didn’t immediately pull off the road is that I suddenly had absolutely zero interest in remaining where I was. All of this is to say, I deeply sympathize with Erica Hite, of Boynton Beach, Florida, who inadvertently captured a rare positive lightning strike on camera and was obviously rattled by the experience.

What makes this strike interesting is that it was positive, not negative, lightning. Positive lightning is much more rare than negative, as this Doppler radar image and accompanying data on lightning strikes from Wxbrad.com makes clear:

The terms positive and negative refer to the polarity of the lightning strike. Typically, lightning transfers a negative charge from cloud to ground. A negatively charged lightning bolt typically carries ~300M volts and 30,000 amps. But unlike negative lightning, which typically originates from the lower portion or middle of a thunderstorm, positive lightning is generated at higher altitudes, 30,000-60,000 feet high. Typically, the insulating layer of negative charge shields the ground from positive lightning strikes. Should this layer be disrupted, a positive lightning strike can result.

Because these strikes begin so high in the atmosphere, they can be significantly stronger and last much longer — up to one billion volts and 300,000 amps. Positive lightning is much rarer than negative, but it kills a far higher percentage of the people unlucky enough to be struck by the bolt. Positive lightning strikes are also responsible for much of the damage to homes, buildings, and other structures hit by lightning in the first place.

“It was crazy. Very scary, very loud,” Hite told the Palm Beach Post. “It was just the right place at the right time. I could probably never in my life get something like that again.”

Probably not. And given just how dangerous positive lightning is, probably for the best. Incidentally, while the bolt is a brilliant red, the color has nothing to do with the fact that it was a positive strike. Lightning color varies depending on local atmospheric conditions and distance from the strike. Lightning is often orange or red for the last few feet of the stroke, which is what we see in the video above.

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