The northern lights depend on luck and weather if that is in your favor than you will be able to see the Aurora Borealis above the inviting streets of Reykjavík. Whether you see the lights or not they depend on two different factors. The first being the weather. If the sky is clear, no clouds, then you are halfway there to seeing the astonishing spectacle that is the Northern Lights (although light pollution can sometimes be a problem). Increased solar activity is the second half so, if these two merge together you may well be able to see the Northern Lights from Reykjavik.