We’ve all been startled by loud claps of thunder during big rainstorms, and likely wondered, what does it mean when thunder is really loud?
Sometimes thunder can be faintly heard in the distance, and other times it’s so loud it feels like it’s shaking the ground you’re standing on.
The varying volumes of thunder have a few explanations. As most people know, it likely originates from nearby if thunder is loud.
A handful of other reasons contribute to the loud, booming thunder that some of us admire, and some of us fear.
There are a few explanations as to what makes thunder so loud. For one, it could be the result of a specific type of thunderstorm. Due to the nature of elevated thunderstorms, thunder tends to be much louder than during surface-based storms.
When lightning hits the ground, you hear thunder. Thunder is the sound that results from a nearby lightning flash.
Thunder serves as a good warning sign to get inside and seek shelter from the storm.
Simply put, lightning causes thunder. The sound of the flash you see is what we know as thunder.
The sound of thunder is created by lightning passing through the air.
As it passes, lightning produces a discharge that heats the surrounding air rapidly.
In a few seconds, it can be as hot as 50,000 degrees, which is five times hotter than the sun’s surface.
Once the flash has disappeared, the air around it begins to cool down and contract.
The rapid expansion and contraction of the air create a sound wave known as thunder.
Thunder can take on a few different sounds, such as:
- A sharp crack, which means the lightning strike was close by
- A rumble, which means the lightning was likely several miles away
- A big boom, which is the sound the main lightning channel makes as it hits the ground
Note: The time between thunderclaps tells you how far the lightning is (5 seconds = 1 mile).
Clouds are composed of tiny droplets of water. Due to the extreme cold temperatures in the sky, the water droplets in clouds begin to freeze and form ice crystals.
As they freeze, they make their way toward the top of the cloud, while the water droplets remain at the bottom.
When ice crystals move past water droplets, they rub against one another and create static electricity.
The static electricity inside clouds causes the ice crystals to take on a positive electrical charge.
The water droplets, however, maintain a negative electrical charge. When it comes to electricity, opposites attract.
When negatively charged electrons from the cloud contact positively charged molecules on the earth, a large electrical current is produced as an onslaught of electrons shoots downwards and creates a bright, visible flash.
The electric attraction between these molecules is so strong that the electrons extend down towards the earth.
This is what happens when lightning strikes.
Note: This static electricity is the same as rubbing a balloon against your hair!
Since thunder is the accompanying sound of lightning, you can’t have one without the other.
Think of it as a cause-and-effect; lightning strikes trigger a temperature change that causes rapid expansion and then contraction, resulting in thunder.
People often see lightning before hearing thunder. You can almost instantly see a lightning bolt from miles away as it strikes the ground.
The sound it makes takes more time to disperse away from the initial point of contact.
Thunder and Electricity
Storms cause positive and negative electrical charges to compile in the space between the ground and the storm cloud, inside the storm cloud itself, or between two other clouds.
When a path between two opposing electrical charges forms, it produces a discharge that we know as lightning.
How Sound Waves Travel
The pattern of sound travel is like a ripple effect; the further you are from the source, the quieter the sound is.
The sound will eventually be gone if you’re far enough from the source.
When lightning hits the ground, it does not merely strike one singular point.
It hits an area, so the sound of thunder does not generate from a single spot.
The sound waves move as a unit through space, so you hear them until the sound from the furthest point passes through.
Thunder generally lasts much longer than lightning.
Due to how sound travels, it will continue to be heard from the furthest point of the lightning channel as stated by the Met Office’s article on thunder.
Sometimes different sounds of thunder can be related to the shape of the lightning as it strikes the ground.
Although thunder alone does not normally harm people nearby, there have been a few cases where the sound of thunder has resulted in injury or property damage.
Weather Online explains that the sound of thunder does not always follow a specific pattern.
Since it is dependent on the shape and location of the lightning strike, it may change in volume or sound type as it continues.
For example, you might hear a loud clap followed by a soft rumble, followed by yet another clap.
There is no way to predict what type of noise thunder will make since it constantly varies according to the details of the lightning that triggers it.
Note: Like tossing a stone in a pond, the closer to the point of contact, the stronger the ripple.
It is likely from an elevated thunderstorm when you hear loud thunder. Elevated thunderstorms rise from warm, moist air directly above the ground.
This air travels upward and forms storm clouds in the sky. Lightning strikes cause sound waves to form near the ground.
These sound waves get pushed back down towards the earth’s surface.
The trapping of sound waves causes them to bounce around and into the ground.
This can cause sound waves to create more sound, amplify the volume of already audible thunder, and make the sound last longer.
When you hear continuous thunderclaps that seem like they’ll never end, you’re likely experiencing an elevated thunderstorm.
Note: We also call the trapping of sound “refraction.”
Surface-based storms occur more commonly than elevated storms. During surface-based storms, sound waves from lightning strikes disperse in all directions.
They don’t get confined to any specific area because there is nothing that holds them in any particular place.
Since elevated storms originate from the ground, they create a temperature inversion as they rise.
They heat the air around them as they rise, making a layer of cold air above the ground.
When lightning strikes, the sound waves get caught between the layer of cold air and the ground, which causes them to bounce into each other.
Being contained in a confined area can cause the noise to be louder since the sound waves are not only dispersing from the point of lightning contact with the ground.
As they bounce off one another and off of the ground, they continue to produce sound waves that are audibly heard as thunder.
Thunder is essentially the sound of lightning so what does it mean when thunder is so loud?
They go hand-in-hand, and understanding where thunder originates makes it easier to see why the volume varies so much and answers the question.
You hear loud thunder from being close to where lightning struck and certain types of storms can also explain storms.
Elevated thunderstorms produce a layer of cold air that traps the sound waves between it and the ground, making thunder exceptionally loud.