No Thunder, All Show: The Magic And Misnomer Of Heat Lightning

Heat Lightning: Here's What You Should Know

You see lightning in the distance and wait for thunder, but hear nothing. Was there a glitch in the matrix?

Not quite. What you’ve just seen is heat lightning.

But there is a gotcha here: heat lightning does not exist!

What You're Actually Seeing: What is commonly referred to as heat lightning is just regular old lightning that is so far away that its resulting thunder doesn’t reach your location. The heat part of heat lightning is added because distant thunderstorms are more common during the summer months and also because people are more likely to be outside in warmer conditions to be able to see the phenomenon.

There really is nothing special about heat lightning.

As a previous Floridian from the Gulf Coast, it was a common experience for me to experience so-called heat lightning during the evening. Thunderstorms often boom during the summer on the Atlantic coast or in the Atlantic, more than 100 miles away. Far enough away that I couldn’t hear the thunder.

Somebody closer to the thunderstorm will hear the thunder.

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This is similar to the old hypothetical “If a tree falls in the woods, would anyone hear it?” The animals in the forest would indeed hear it, but somebody outside of the forest won’t because they are too far away.

Since heat lightning is generally scores of miles from your location, it is less likely that you'll be struck by it.

That said, storms often move and can come closer to your location, or new thunderstorms can bubble up over your community.

If you hear thunder, you should immediately move indoors.

Other Silent Thunderstorms: Distance isn’t the only reason that thunder may not be heard after lightning.

Mountains, hills or well-foliaged trees can help mute the sound of thunder.

The atmosphere itself may carry light, or even sound, farther from a thunderstorm than usual. If you’re in the right spot, a shield of clouds may reflect some of the light closer to you than if there weren’t clouds.

Conversely, if there is a layer of warm air aloft (called an inversion), the sound waves from thunder may carry farther than is typical since the sound gets trapped closer to the ground. This is not heat lightning, but rather just a little extra for you to share.

Jonathan Belles has been a graphics meteorologist and writer for weather.com for 8 years and also assists in the production of videos for The Weather Channel en español. His favorite weather is tropical weather, but also enjoys covering high-impact weather and news stories and winter storms. He's a two-time graduate of Florida State University and a proud graduate of St. Petersburg College.