Does the pH reading of water depend on the temperature?

Answer

The pH is indeed dependent on the temperature. At 20°C, the pH of pure water is 7, as you probably know. However, at 10°C it becomes 7.27 and at 30°C the pH of pure water is 6.92. Moreover, the measurement of pH is also temperature sensitive. So there are indeed temperature effects, but the effect is not very strong as long as you do not measure at very high or very low temperatures. For many applications, the difference makes little difference.

If you want to be accurate, it is therefore best to always carry out your measurements at the same temperature. For example, you put your sample in a room until it is about 20 °C warm.