Earth is closest to the sun when the northern hemisphere has winter. Closer distance means less chance for random particle showers from the sun to miss Earth. The next thing is the light conditions. Full moon means weak auroras will hardly be visible, and stronger auroras will look weaker. So given those factors, new moon periods from September/October to March/April will likely be best. And in my experience, activity seems to be highest 8-10/11 PM and then maybe come back again 2-3 AM (I am very seldom watching at those hours, but I've heard photographers getting great shows after I have given up and gone to bed). Those hours might be specific to my latitude (63.43˚), I don't know.
Then you have the conditions you have no control over - cloud coverage, and solar prominences. There is lots of monitoring info of solar prominences available, and you can find information about prominences facing Earth which will likely cause solar storms on Earth probably 3-5 days ahead of time, likely more. And that's about as far as I thrust "long-term" weather forecasts as well, so if you have to travel far to get far enough north to observe auroras, then you should monitor those situations and have your air-travel-approved grab-bag ready...
Bookmarks