Northern Lights planner — Iceland aurora odds by month
The Northern Lights (aurora borealis) are visible in Iceland from September to April when nights are long enough. You need darkness, clear skies and solar activity (KP index). You cannot control the weather, but you can pick the right month.
| Month | Darkness | Typical KP | Odds | Notes |
|---|---|---|---|---|
| September | 13 h | KP 2–3 | 3/5 | Season opens. Odds rising. Combine with golden autumn landscapes. |
| October | 10 h | KP 2–4 | 4/5 | Good odds, fewer tourists, dramatic storms add atmosphere. |
| November | 6 h | KP 3–5 | 4/5 | Long dark nights — excellent for aurora. Cold and quiet. |
| December | 4 h | KP 3–6 | 5/5 | Best month: max darkness (only 4 h daylight). Book aurora tours early. |
| January | 5 h | KP 3–6 | 5/5 | Peak aurora season continues. Snow adds drama. Ice cave tours open. |
| February | 8 h | KP 3–5 | 5/5 | Still prime. Equinox effect boosts activity mid-Feb. Ice caves open. |
| March | 12 h | KP 2–5 | 4/5 | Spring equinox boosts geomagnetic activity. Last ice cave month. |
| April | 15 h | KP 2–3 | 2/5 | Season closing. Dusk comes later — less usable dark sky each week. |
| May–August | <2 h | — | 0/5 | Midnight sun: too bright to see aurora. Not possible late May–mid Aug. |
Chasing tips
- Get away from Reykjavik light pollution — even 30 km east along the Þingvellir road makes a big difference.
- Check the Aurora Forecast app (Vedur.is) or the Space Weather app for KP predictions 1–3 days ahead.
- KP 3+ is ideal for Iceland — at high latitudes even KP 2–3 can produce visible curtains on a clear night.
- Book a guided aurora tour from Reykjavik — guides track cloud cover in real time and drive to clear skies.
- Stay patient — cloudy nights happen; most aurora tours offer a free rebooking if skies are overcast.