Tire temperature
Tire temperature is how hot a tire's tread runs, usually measured across inside, middle and outside to judge grip and setup.
Also called: tire temps, pyrometer readings
Tires have an operating window. Too cold and the rubber is hard and slippery; too hot and it gets greasy and wears fast. Track drivers measure tread temperature right after a session, ideally with a probe pyrometer at the inside, middle and outside of each tire.
The pattern across the tread tells a story. Hotter in the middle points to over-inflation; hotter on both edges points to under-inflation. A hotter inside edge often reflects camber, which is normal in moderation. Comparing front and rear temperatures can help explain understeer or oversteer.
Measure quickly, before temperatures equalize, and do it in the same order each time. Cold tires early in a session also deserve respect: the first laps should build heat gradually rather than diving into the first corner at full commitment.
Keeping tires in their temperature window maximizes grip and helps you tune pressures and alignment.