Aurora tonight in Rovaniemi
Clouded out — 100% cloud at best between 22:12 and 04:08.
Checked against NOAA SWPC, the FMI magnetometers and the FMI cloud forecast.
On the Arctic Circle. Quiet nights are enough; the usual problem is cloud, not activity. No polar night here — refraction lifts the sun over the horizon even on the shortest day.
The evidence
- Geomagnetic activity
- Kp 3.67 (unsettled) NOAA SWPC, estimated Kp, 4 minutes agoForecast peak Kp 2.67 during the dark hours NOAA SWPC 3-day forecast, issued 03:30 EEST5% chance of aurora overhead NOAA SWPC OVATION, 9 minutes agoLocal disturbance 4 nT/min at Ranua, 74 km away FMI magnetometer network, 54 minutes ago
- Cloud over the dark hours
- 100% cloud at best around 22:00, 100% at worst FMI HARMONIE forecast, covering 22:12–04:08
- Darkness
- Astronomical dark 22:12–04:08 (5h 56m) computed here from the date and the coordinatesSunset 19:03, sunrise 07:14 computed here
- Moon
- Full moon, 100% lit, 20° above the horizon at the start of the dark hours computed here
Finland's all-sky aurora cameras are run by the Finnish Meteorological Institute at Sodankylä, Muonio, Kevo and Nyrölä. FMI does not publish those images under a licence that lets us embed them, so we link instead: Auroras Now!. See where the data comes from for what we checked.
Get an alert when Rovaniemi clears
Not open yet. The alert will send one email on the evenings when it is dark, the cloud has broken and the field is active enough for Rovaniemi — and nothing on the other nights. It is not taking addresses until it can actually send, because a sign-up box that stores nothing is worse than no sign-up box. Until then, this page is the answer.
What the numbers mean
Four things have to line up before you see anything, and three of them are on this page above. The fourth is your own eyes adjusting, which takes about twenty minutes in real darkness and does not survive a glance at a phone.
Darkness comes first because it cannot be argued with. The aurora is always there when the field is active; you can only see it once the sun is more than 18° below the horizon, which is what the dark band above marks. In Rovaniemi that is 5 hours and 56 minutes tonight.
Kp is a global index of how disturbed the Earth's magnetic field is, from 0 to 9, published every three hours. It is a blunt instrument: it says the whole planet was disturbed, not that the aurora is over Rovaniemi now. At 67°N the auroral oval usually sits overhead already, so a quiet Kp is no reason to stay in.
The local disturbance is the better number, and it is the one most aurora pages do not have. FMI runs magnetometers across Lapland; we take the rate of change of the horizontal field at the nearest one, in nanotesla per minute. A field moving fast overhead means current flowing overhead, which is the aurora itself. Above roughly 40 nT/min it is usually visible; above 100 a substorm is running and it will be moving.
Cloud ends most attempts. The figure above is the total cloud cover FMI's HARMONIE model forecasts for the dark hours, at these exact coordinates. Anything over about 70% and you will not see through it; under 30% and it stops mattering.
The moon does not stop the aurora. A full moon high in the sky washes out the faint green arcs that make up most displays, so a strong night still shows and a marginal one does not.
Getting there tonight
Rovaniemi to Saariselkä and Inari: Normal driving conditions on Rovaniemi to Saariselkä and Inari — the surface runs +7.5 to +9.4 °C. · Oulu to Rovaniemi: Normal driving conditions on Oulu to Rovaniemi — the surface runs +9.4 to +10.8 °C.
Nearby
Also on this site: how the daylight changes through the year, and the other five places.