Why does my tyre pressure light come on in the morning and go off later?

Cold air lowers the pressure overnight, by roughly 1 psi for every 5 to 6°C. Driving warms the tyres and the pressure rises again, so the light can go out. The tyres are still low when cold, so top them up to your car's figures.

Should I put more air in my tyres in winter?

Set them to your car's normal cold figures, checked when cold. The cold lowers the pressure, so in winter you'll usually need to top up more often. If you've fitted winter tyres, check whether your handbook gives separate figures.

How much does tyre pressure drop in cold weather?

About 1 psi for every 5 to 6°C the temperature falls. A drop from 18°C to freezing takes off around 3 psi.

Seasonal

Cold mornings and the tyre pressure light

4 min read · Updated 4 October 2026

Every autumn it catches people out. The first cold morning, the tyre pressure warning comes on, and the tyres look fine. Usually there's nothing wrong with them except the weather. But that doesn't mean you can ignore it.

What's happening

Air shrinks as it cools, so the pressure inside a tyre drops when the temperature does: roughly 1 psi for every 5 to 6°C. Tyres set on a mild September afternoon at 18°C can be around 3 psi lower on a 0°C morning. Add the 1 psi or so that every tyre loses each month anyway, and that's often enough to trip the warning.

That's also why the light sometimes goes out after a few miles. Driving warms the tyres, the pressure climbs back up, and the system stops complaining. It'll be back tomorrow morning.

Does it matter if it's just the cold?

Yes. The pressure figures for your car are cold figures, so a tyre that's low on a cold morning really is low. Through the winter, that's most of the time. And it's the time of year when you most need the grip: wet, cold roads, leaves and the odd frost.

How to top up in winter

Check them cold, outside. First thing, before you drive. If you pump them up in a warm garage and then drive out into a frost, they'll drop again.
Set them to your car's normal figures. The cold doesn't change what the right pressure is; it just means you'll need to top up more often. If you've fitted winter tyres, check whether your handbook gives a separate figure for them.
At a forecourt after a drive, the tyres read high. Set them to the figure anyway, then check again cold the next morning and top up if they've dropped.
Reset the warning if your car needs it. Many cars, including most Volkswagens, Peugeots, Fords and Fiats, need telling that the pressures are right. Here's how to reset it on your make.

Kit that makes it easier

Tyre inflatorSet the pressure, press start, and it stops by itself when it gets there. No trip to the garage, so you can top up while the tyres are cold, and most show the pressure as they go.
Our pickMichelin 12V digital tyre inflator (9519)Plugs into the car's 12V socket, so it's never flat when you need it. Dial in the pressure and it switches off when it gets there.See it on Amazon
Prefer cordless?Ring TyreInflate Go 4 cordless inflatorNo lead to the car, but it needs charging, and the battery won't last forever.See it on Amazon
Or see other inflators
Pressure and tread gaugeOnly needed if your inflator doesn't show the pressure, or to double-check a forecourt machine. A good one reads tread depth too.
Our pickMichelin rechargeable digital tread and pressure gaugePressure and tread depth in one, and it's rechargeable, so no button batteries to replace.See it on Amazon
Or see other gauges

As an Amazon Associate, Right Pressure earns from qualifying purchases. It costs you nothing extra, and no brand pays to be mentioned here.

When it isn't just the cold

One tyre is much lower than the others. The cold affects all four the same, so a single low tyre points to a leak. Here's why a tyre keeps losing pressure.
The light comes back within days of topping up. Same again: something is letting air out.
The light flashes for a minute, then stays on. That's usually a fault with the system, not the pressure. A garage can read the sensors.

On an electric car, soft tyres in winter take range on top of what the cold already costs, so it's worth keeping on top of them.