Use vedur.is to check the weather:Aurora forecast: https://en.vedur.is/weather/forecasts/aurora/. anything => kp3 is interesting. If you get to >kp5, be ready to not sleep to be in a clear spot, to enjoy as much as possible. If you are up north, even a kp1 can provide good auroras.

And if possible keep some night without hotes (so you can book last minute to get to be at a location with clear sky).

Good luck ! March is usually amazing for auroras!