You’re driving down the highway and decide to let in a bit of fresh air. You roll down one of your windows, and suddenly it’s like a freight train is running right next to your car. The overwhelming, rhythmic “thumping” sound feels like it’s about to blow out your eardrums.

We’ve all experienced it. But what is it?

That’s wind buffeting ‒ a loud and annoying phenomenon that happens when you roll down a lone window in your vehicle. But why does that happen, and what can you do to stop it?

Let’s find out.

3 Facts About Wind Buffeting

1. It’s Caused When Two Pockets of Air Crash Together

Get ready for some science. Wind buffeting is caused by an occurrence known as Helmholtz Resonance. In a nutshell, when you open just one window in your vehicle ‒ or the sunroof or moonroof ‒ the air inside your car thumps up against the faster-moving air outside the window.

When they clash, these two bodies of air compress and decompress over and over again. The result? Small wind vortexes that create that loud thumping sound.

These factors can affect wind buffeting:

• The size and shape of your vehicle: You’ll hear louder thumping from newer, aerodynamic cars compared to older, boxy models. (More on that below.)
• Your driving speed: The faster you drive, the more noticeable and extreme the noise.
• Back vs. front windows: Wind buffeting is worse in back windows, since your front windows have side mirrors to help redirect the airflow.

2. It’s More Common in Newer Vehicles

New cars are more aerodynamic than their older cars. That means their shape and design help them move through the air more easily, reducing overall drag.

Unlike older vehicles, they’re also constructed to keep air sealed inside the vehicle rather than letting it escape ‒ or enter. It’s great for fuel economy, among other things.

But with all that air closely hugging the exterior of newer vehicles, any kind of opening – like your backseat window – will interrupt that smoother airflow and cause that thumping sound.

See also: How to Get Better Gas Mileage (And Other Questions About Fuel Economy)

3. It’s Pretty Easy to Fix

Want the thumping to go away? Just open another window to help stabilize the air pressure. Voilà!

If only all other car annoyances were so easy to solve (we’re looking at you, flat tires).

Feel Right at Home

From the position of the steering wheel to your favorite station on the radio, your car is your safe haven on the road ‒ even with a little wind buffeting along the way. We want you to feel just as comfortable with your auto insurance coverage.

Get a no-obligation quote from a local car insurance agent near you today.