The northern lights are the lure that draws on most of Iceland's visitors in winter but not all are lucky enough to see the lights on their first or even second trip to Iceland. To help improving your odds and happiness index on your travel in Iceland's winter we put together a shortlist of things to keep in mind.
1. Weather - Be flexible
This is the single most critical factor on your hunt for the Northern lights in Iceland. The weather changes very fast and there can be days with nice clear skies that then turn into fully overcast evenings and of course the other way around. Luckily the overcast usually doesn't cover the whole island. There may be clear skies in Akureyri, Ísafjörður, Egilsstaðir or Stykkishólmur even though it is poring with rain in Reykjavík (Sitting at home writing this I see from vedur.is that the skies are clear in all those places except Reykjavik).
If seeing the lights is the main purpose with your visit, then you should go and spend the night there. I realize that cost is a concern but usually a short notice booking in those places is a welcome addition to the low season in winter and the room might even be offered to you at a discount.
2. Kp index
This is a short one. Don't pay too much attention to the Kp index unless you really know what you are looking at. I have seen good polar lights when the Icelandic Met office graded the Kp at 0 and I have stayed out for hours with Kp at 8 without seeing more than just the stars and the headlights from other cars.
When we decide whether to go out for a tour or stay at home we look at this site here: https://www.swpc.noaa.gov/products/3-day-forecast it is a "long" term forecast (3 days:-) and it gives you an idea of what to expect. Then when we are out on the road hunting for the northern lights we talk to other guides and we even have a member of the staff in front of the computer monitoring the magnetic measurements of the Met office and other sites to stay on top of things in case the lights decide to make an appearance.
3. Happy index
This one is dedicated to the expectations as we have seen guests being disappointed with the lights that they see, even when the lights are well above average. The Northern lights are a natural phenomenon and the intensity varies but most pictures shown on the internet and social media are pictures of the awesome firework show that the solar winds put on every once in a while. In the real world it can be quite different. Sometimes the lights appear just like faint white cloud in the distance and you can only confirm that these are indeed the northern lights when you look at the picture in your camera (if that happens to be the case on your tour ask your guide if there will be a rerun. Most tour operators offer a second chance if no lights are seen on the first tour).
The length of the display of the aurora borealis can also vary and sometimes the show lasts for hours and other times it doesn't last long enough for you to get as much as a picture.
Talking about pictures, don't try to learn how your camera operates on the tour unless you like the challenge of working under pressure with hands numb from the cold and 10% power left on your camerabattery. You might end up missing the show and for no reason as your guide will have a camera and a tripod and he or she will be more than happy to take your pictures snf send to you the morning after. After all the hard work and travel we really want you to enjoy the show.