Lightning out to sea near Tunisia (photo from Wikimedia Commons)

2 July 2025

In the hot days of summer we sometimes see lightning in the clouds at night but hear no thunder. Though it’s not an accurate name we call it “heat lightning.”

Here’s what it is, paraphrased from Wikipedia: Heat Lightning.

Heat lightning is a misnomer for the faint flashes of lightning on the horizon or among the clouds from distant thunderstorms that do not seem to have accompanying sounds of thunder. Heat is not causing silent lightning. Instead the lightning is so far away that the thunder dissipates before it reaches the observer. At night, it is possible to see the flashes of lightning from very far distances, up to 100 miles (160 km), but the sound does not carry that far.

Last Friday as Donna Foyle and her family watched some distant fireworks, the clouds put on a better show. She captured both in this video. How cool!

Why can’t we hear the thunder? A video from Iowa’s Local 5 Weather Lab explains. Click on the red play button to see it on YouTube(*).

screenshot from What is Heat Lightning on Local 5 Weather Lab on YouTube
Click on the image to see the video

(*) Local5 Weather Lab does not allow embedding of this video.