Normal Temperature
It really bugs me when TV weatherman talk about the "normal temperature" for today. The temperature they are talking about would never be the "normal" temperature, unless they are talking about the most commonly observed one. Average is not the same as "normal". You could plausibly have an average temperature that has never actually been observed as the high on that day. It's just technically incorrect, and yet I hear it almost every night. It just bugs me, you know.