Please,
How good idea or not is to take the Hurtigruten coastal voyage to see the northern ligths, meaning that at sea it won't be the driest climate conditions,
Also how good idea or not is to take at the begining of November, meaning that won't be the driest climate conditions,
Last, for the lights, is it worth it to take from Bergen or it is a waste till the Polar Circle.
Thank you very much for input.
If your main focus is the Northern lights then I would skip the Hurtigruten and fly directly to Tromso. There are several boat/NL expeditions offered directly from there. As well as dog sledding/NL, snowmobile/NL etc etc combos. I didnt manage to do it when I was there, but the options in the Lyngen Alps looked awesome (obviously its better out of the "Tromso city" without the light pollution).
So although I am sure the trip from Bergen north is great, you are right that it is far from optimal if your main aim are the aurora.
I can't speak for Hurtigruten coastal voyage, though I imagine must be beautiful, but Tromso is a really good choice re aurora.
Why isn't November dry?
According to this it is the second wettest month of the year in Tromso, behind October and slightly ahead of December: http://en.wikipedia.org/wiki/Tromso
Basically the autumn is wet in NW Europe because the sea is still fairly warm, so evaporating a lot of moisture, and is then encouraged to release that moisture onto the land as rain (or snow) because the land is cooling down fast, so the moist air cools as it moves over that land. In early winter, the local evaporation is reduced, but weather systems continue to arrive from warmer waters further to the SW, so it stays fairly wet. But late in the winter the sea is cooler even in the further south parts of the temperate circulation zone, so there is less evaporation to deliver rain. Spring is generally the driest time of year in NW Europe. In contrast, it is a rather wet time in SE Europe. I'm not sure I want to work out why that is just now.
Alta in Finnmark has a rather drier climate, because it is protected by the mountains to the W and SW.
My point is you can see the northern lights in November.
Also October, December, January, February, March, April. It doesn't matter when you go, you could stay an entire winter, be up all night every night and never see them or see them every night. You can't predict this, doesn't matter if it's dry or not, but it's better.
My point is you can see the northern lights in November.
Indeed. But the main impediment to seeing the Northern lights, especially in this active stage of the sunspot cycle, is clouds. So you improve your odds of seeing them if you go at a less cloudy time of year. Rainfall isn't perfectly correlated with cloudiness, but it's a fair indication.