Thank you, @alnedkov! :)
Aurora depends on so many factors that it isn't possible to predict it at 100%. There are certain apps that show the probability based on your location but speaking from my experience, they are not reliable at all ;)
Aurora could glow any night of the year in theory, but the best months to see the Northern Lights are October and November and then February and March. That's based on statistics collected for several years back.

I have to admit I saw it in the end of August during my photo trip in Iceland and it was an absolute surprise even to the Icelanders ;) I was there for 8 days and Aurora was on one night only.