I am planning a trip next March or April to go see the Northern lights. I need some help trying to decide the best dates. We can go Feb 28-March 8 to Norway or April 10-18 to Norway or Iceland. I’m afraid there will be more cloud cover in the Feb 28 to Norway trip. But, there will be shorter days and longer nights, meaning more opportunity to see the lights. I think all things being equal, I had rather visit Iceland than Norway, but I don’t know why I think that. Also, the flight schedules are better for Iceland. But that would just be the tie breaking vote, not a deciding factor. Anyone have any thoughts on which dates and locations would be better for viewing the Aurora Borealis??
Actually, look at the sky tonight, from wherever you are. If the sky is clear, there's a good chance of seeing them. Seriously.
Seattle Times: Northern lights may be visible this week from Western WA
As to your specific question: There's no meaningful way to answer your question, because there's very little qualitative difference between early March versus Early April, and Norway versus Iceland. There are other factors, most of which are completely beyond your control, that might make a difference....or both could be equally good (or equally bad). There's no way to know.
Flying half-way around the world to spend a week hoping to see the northern lights is making a bet (and an expensive one). You may or may not see anything better than what you can see from your backyard tonight.
If you really want to go somewhere, go where you would prefer to be if you knew you were not going to see anything in the sky. Because there's a good chance that's going to be the case. If you're there, and you do get to see the northern lights, then all the better. But don't hang your hopes on nature cooperating.
More here: Northern Lights
Fairbanks, Alaska. Look it up for northern lights.
Best view to actually "see" the Northern Lights is supposed to be thru a good Camera. The Human Eye evidently can't see all the spectrum. You really need a low horizon on flat land facing north with a "dark sky" situation. I saw them once between the Columbia River and Spokane. Right now they are being caused by Solar Flares.
I've been to Iceland three times to try to see the Northern Lights. All three times there was cloud cover and rain. I was told, since it's an island, it will be cloud cover more so than other places.
As to when to go, it can't be predicted in advance. It depends on activity and weather.
Next try for me will probably be either Northern Norway or Sweden.
April is really too late for the Northern lights, you might see them if you are lucky but it will only be dark enough for a pretty short period each day and you need to stay up late.
Visiting Iceland is not a bad idea, it's an amazing country in many ways. But it is not a good place to visit for the northern lights. As mentioned the maritime climate means a large risk of clouds obstructing the views. Norway would be a slightly better choice for that reason. But to be honest, Sweden would be even better. Abisko is a popular place to see the lights, and for a reason.
You don't mention your location in your profile, but I'm assuming you are from North America. In that case, if your goal is just to see the lights, maybe somewhere in Canada is a better option to be honest.