Extreme Aurora Borealis has been predicted over northern hemisphere:
http://www.gi.alaska.edu/AuroraForecast/2 - Northern America
http://www.gi.alaska.edu/AuroraForecast/3 - Nordic countries
It should be visible from 5pm GMT and the coming 24 hours all the way down to Copenhagen, Edinburgh, and Moscow in Europe and Boston and Seattle in the Northern America. Unfortunately, nights in Norway are too bright at this point to see it. :\
The cause of this is a huge explosion that occurred on the Sun 7th June.