Several factors need to come together for you to see the Northern Lights. Most importantly, you need dark, clear skies – and then it depends on the intensity of the geomagnetic activity. It’s possible to see them from late August through to early May, but October to March is the prime window of opportunity due to the longer nights. Generally, avoiding light pollution makes it much easier to see the aurora, but during a strong display, you may be fortunate enough to see them in central Reykjavik. Consider booking a specialist tour which will take you out of town to an observation spot where you’ll have the best possible chance.