Aside from big storms this week, temperatures will drop significantly, which may prompt the tire pressure sensor light to turn on. The science behind it could help you avoid that trip to the tire place.

It’s all about the air’s density. Warm air is lighter, and it expands. Think about a hot air balloon. Air is warmed to help the balloon fly.

On the other hand, cold air is denser, meaning heavier, sinking and contracting. Think about an ice cube; particles come closer together, contracting. The opposite is true for warm air, when particles move around more freely, warming and expanding.

Your tire’s air reacts the same way. When temperatures drop, the particles contract, triggering the sensor light to come on. Take the measurement. If your tires were low before, inflate them. If they were not low before, you might not have to go get them checked. Don’t overinflate your tires.