finger to the wind

A focus on or awareness of current trends. If you're going to be a good teacher, you need to have your finger to the wind, so that you can relate to your students and understand what is important to them. The senatorial candidate fired his campaign manager when it became clear that she didn't have a finger to the wind. How should I know what's cool? You should talk to my teenage daughter, I'm sure she has her finger to the wind.