Northern lights in Tromsø tonight
One live call for Tromsø — the Kp, tonight's dark window, the oval, the cloud — then the inland day trips the tours head for when the coast is clouded, each with its own verdict tonight, and the book's two places in Troms, each with its own page and photograph.
Reading the field under the auroral oval…
How it works
A magnetometer measures the Earth’s magnetic field. When a substorm surges the electric current that runs about 100 km up along the auroral oval, the field on the ground beneath it drops by hundreds of nanotesla (nT) within minutes — the sharp dip a magnetogram shows.
This reads the nearest of the Finnish Meteorological Institute’s eight magnetometers, Kilpisjärvi, against its own last 24 hours: 150 nT either way is active, a 300 nT drop a substorm, 600 a strong one. It measures the sky over the station — up to about 300 km away it still speaks for yours — and says nothing about cloud. Kp and Hp30 are planetary; this is local, and minutes old.
- 7.9 h
- 8.0 h
- 8.2 h
- 8.3 h
- 8.4 h
- 8.6 h
- 8.7 h
Darkness (astronomical, −18°) and the moon are astronomy — exact for all seven nights. Kp is NOAA's forecast peak over each dark window and cloud is Open-Meteo's mean; both reach about three nights out (3 of 7 here), the rest read “—”. Kp 1+ is this spot's own horizon threshold. Whole-season calendar →
Tonight around Tromsø
The Lyngen Alps — the favourite day trip, about 1.5–2 h with a short ferry.
Beyond the Lyngen Alps on the E6, about 1.5–2 h — where tours head when the coast is clouded.
Over the border in Finland, about 2.5–3 h — the long escape from coastal cloud.
Each from its own watch point, as on its page: NOAA's Kp, Open-Meteo's cloud over that spot's dark window tonight, and its darkness. Times are local.
Each place, its own page
The headland north of Harstad — drive the Fv2 to its very end. Little traffic, a broad, low northern horizon.
On the Tromsø–Alta E6, just past Skibotn — a panoramic view of the Lyngen Alps across the fjord.
The 6 places, west to east
- Elgsnes68.92°N 16.26°Enorth of Harstad · low horizon
- Tromsø69.65°N 18.96°Ethe city · dark spots a bus ride out
- Lyngen69.58°N 20.22°Ethe Alps · favourite day trip
- Lyngenfjord69.44°N 20.27°Ethe book's frame · E6 lay-bys
- Skibotn69.39°N 20.27°Einland valley · where tours go
- Kilpisjärvi69.05°N 20.79°EFinland · the long escape
Cloud cover by month · the whole region
Clearest dark months here (outlined): Jan, Mar, Oct. Faint: no night with an hour of astronomical darkness — midnight sun (Jun, Jul); white nights, twilight only (Apr, May, Aug). Part-faint months are dark on some nights only: dark until 24 Mar; dark from 17 Sep. ERA5 reanalysis, 2015–2024 monthly mean. Climatology, not a forecast — a regional ~25 km grid; local microclimates are not captured. Darkness & moon calendar → Best month, all spots →
Tromsø in numbers
Kp is a global index; the thresholds come from Tromsø's geomagnetic latitude (67°). Historical odds from the GFZ definitive record, the last 365 days.
From the book
Questions people ask
Can you see the northern lights in Tromsø?
Yes. From a dark spot you need about Kp 1 for a faint glow on the northern horizon and roughly Kp 3 for aurora overhead. Tromsø sits at about 67° geomagnetic latitude, under the auroral oval — so on most nights the limit is the cloud, not the Kp.
Is it clearer in Lyngen, Skibotn or Kilpisjärvi?
Not on average — ten years of ERA5 cloud make the inland valleys no clearer than the coast. But an average isn't the night you're out: when a front sits on the coast, the mountains often hold it on the sea side, and that is where the chase tours head on bad nights. The board above reads tonight's cloud at each.
When is the aurora season in Tromsø?
It is dark enough for a bright display from about 1 September to 10 April, and fully dark from mid-September to late March. Polar night, about 28 November to 14 January, means no sunrise, not twenty-four hours of dark. November and December are the cloudiest months in the ten-year record; the strip above has every month.
Should I drive or take a tour?
If you haven't driven on ice in the dark, take a tour, or the bus to a darker spot outside the centre — on a clear night a strong display is easily seen from Tromsø itself. If you do drive, never stop on the road for the lights: use a proper lay-by, with parking lights on, not hazards. Wear a reflector, and stay off private land and lake ice.