It is a misconception that heat lightning is caused due to heat or hot and humid weather. Similar to ordinary lightning, it is caused due to a thunderstorm.

Heat lightning is a commonly misused and misinterpreted term. It is used for the flashes of light seen in the sky near the horizon. Is it one of the types of lightning? It is caused due to heat? Sometimes it is even argued that no such thing as a heat lightning exists. Let us find answers to these questions and know more about this mysterious phenomenon.

What is Heat Lightning?

Sometimes during a storm, you can see lightning strike, but cannot hear the thunder as there is large distance between you and the storm. This is known as heat lightning. As there is no audible sound of thunder, the lightning is just seen as a flash of light.

As the lightning takes place far away, the sound waves get dispersed while traveling and do not reach the observer. Heat lightning is nothing but ordinary lightning, minus the sound of thunder. It is a term used to describe flashes of light that are seen near the horizon. As light flashes can travel to a larger distance than sound waves, only the flashes of light are seen, but the thunder is not heard.

Facts About Heat Lightning
  • It occurs in summers and specially on hot summer nights. Hence, it is named so.
  • It is not followed by thunder and rainfall like ordinary lightning. The thunder and rainfall actually take place at a distance, hence, are not observed.
  • The Earth's curvature, airborne elements like snow or dust, etc., can muffle the sound of the thunder.
  • Heat lightning can be seen all over the world. It is especially common in the mountainous regions.
  • It is usually an indication of an approaching storm.
  • Many lightning casualties occur in the summer months. But, chances of being struck by lightning can be prevented if you follow safety rules.
  • Just because you cannot hear the thunder, does not mean you are not at a risk of getting stuck by the lightning. Remember that light travels faster than sound.
  • Light travels much faster and to a farther distance. Hence, a lightning can be seen but a thunder cannot be heard if the distance is too great.
Some Myths and Facts

Myth: Heat lightning is a type of lightning.
Fact: It is ordinary lightning, appearing like a flash of light, without any sound.

Myth: Heat lightning is caused due to heat or hot weather.
Fact: The term 'heat lightning' is a misnomer. It is not caused due to heat or hot weather. It is, however, observed in warm seasons.

Myth: As heat lightning occurs only in summer, it is not dangerous.
Fact: It is caused due to thunderstorms. Although the thunder is not heard, it is an indication of an approaching storm.

Is Heat Lightning Dangerous?

As observed in the aforementioned facts, you should remember that heat lightning is equally dangerous as ordinary lightning. Many people enjoy watching the brilliant orange flashes of light near the horizon. But it is advised to immediately seek shelter indoors. As mentioned above, it is an indication of an invading storm, and people may not realize how close the storm is and may be under risk of getting struck by the lightning. Specially in the mountainous regions, the lightning is closer than it appears which may confuse the observer. Due to the presence of mountains, the sound of thunder get muffled and is not heard even if the storm is in the close proximity.

Lightning Safety Measures

Always remember when you see lightning, always stay indoors or safe. If you are outdoors, it is best to stay in your car or seek shelter in nearby buildings. Avoid standing under a tree or seeking shelter in very high buildings. If you are on a hilltop, try to seek shelter as you are at a higher risk of getting stuck with lightning. One should also stay away from electrical poles or telephone lines. It is even advised not to use plug-in electrical equipment for safety reasons.

Heat lightning is for real. However, it is not any strange phenomenon, just the regular lightning, without the sound of the thunder. The next time you see a heat lightning, be careful and look for your safety first!