Comparison
Tornio vs Jakobstad for the northern lights
Answer
Side by side
| Figure | Tornio | Jakobstad |
|---|---|---|
| Dipole latitude | 63.2° | 61.4° |
| Kp for the oval edge overhead | Kp 2 | Kp 3 |
| Civil night, December 15 | 17.5 h | 16.9 h |
| Dark-season days | 259 | 273 |
| Nights with no civil darkness | 84 | 66 |
| Dark-month cloud, NASA POWER | 76% | 77% |
| Solar midnight, December 15 | 00:18 | 00:24 |
Tornio sits at 63.2 degrees geomagnetic, inside SWPC's 60 to 75 degree band, where aurora can be seen on more than half of all nights. No storm is needed: by SWPC's rule the average oval edge is overhead at Kp 2. Jakobstad sits at 61.4 degrees geomagnetic, inside SWPC's 60 to 75 degree band, where aurora can be seen on more than half of all nights. No storm is needed: by SWPC's rule the average oval edge is overhead at Kp 3.
Civil night month by month
On December 15 Tornio has 17.5 hours of civil night and Jakobstad 16.9. Across the 15th of each month, Tornio is darker in 5 months and Jakobstad in 5. The widest gap comes in May, when Jakobstad has 2.0 more hours.
| Month | Tornio | Jakobstad | Difference |
|---|---|---|---|
| January | 16.6 h | 16.0 h | +0.6 h |
| February | 13.6 h | 13.4 h | +0.2 h |
| March | 10.4 h | 10.5 h | -0.1 h |
| April | 6.4 h | 6.9 h | -0.5 h |
| May | 0.0 h | 2.0 h | -2.0 h |
| June | 0.0 h | 0.0 h | +0.0 h |
| July | 0.0 h | 0.0 h | +0.0 h |
| August | 4.5 h | 5.4 h | -0.9 h |
| September | 9.0 h | 9.3 h | -0.3 h |
| October | 12.5 h | 12.4 h | +0.1 h |
| November | 15.7 h | 15.3 h | +0.4 h |
| December | 17.5 h | 16.9 h | +0.6 h |
Season and midnight sun
Tornio has no civil darkness from May 10 to August 1, 84 nights in 2026, and its dark season, 4 or more evening hours of civil night, lasts 259 days. Jakobstad has no civil darkness from May 19 to July 23, 66 nights in 2026, and its dark season, 4 or more evening hours of civil night, lasts 273 days.
Distance, cloud and time zones
The two towns are 251 km apart by great circle. In the dark months both average about 77% cloud in NASA POWER's 2001 to 2020 record. Tornio's best month by civil night times clear sky is January. Jakobstad's best month by civil night times clear sky is March. Time zones: Europe/Helsinki and Europe/Helsinki.
For tonight, open the live pages for Tornio and Jakobstad, which carry the live OVATION cell.
Questions
- Is Tornio or Jakobstad better for the northern lights?
- Tornio sits closer to the oval, at 63.2 degrees geomagnetic against 61.4. Darkness, cloud and your dates decide the rest; the tables on this page show both towns month by month.
- Which has longer nights in December, Tornio or Jakobstad?
- Tornio, with 17.5 hours of civil night on December 15 against 16.9 in Jakobstad.
- What Kp do Tornio and Jakobstad need?
- By SWPC's rule of 66 degrees at Kp 0 and 2 degrees per step, Tornio needs about Kp 2 and Jakobstad Kp 3 for the average oval edge to sit overhead.
- When is it too light for aurora in Tornio and Jakobstad?
- Tornio: May 10 to August 1. Jakobstad: May 19 to July 23.
- Which is clearer, Tornio or Jakobstad?
- Tornio, with 76% mean cloud in the months with 4 hours or more of civil night against 77% in Jakobstad (NASA POWER, 2001 to 2020).
Sources and verification
- IGRF-14 coefficients, NOAA NCEIhttps://www.ngdc.noaa.gov/IAGA/vmod/coeffs/igrf14coeffs.txt
- SunCalchttps://github.com/mourner/suncalc
- GeoNameshttps://www.geonames.org/export/
- NASA POWER climatologyhttps://power.larc.nasa.gov/docs/services/api/temporal/climatology/
- NOAA SWPC, Tips on viewing the aurorahttps://www.spaceweather.gov/content/tips-viewing-aurora
Quoted figures last checked against their sources on 2026-09-30; next review 2026-12-31. Computed figures come from SunCalc and the IGRF-14 dipole as described in the methodology. Every quote is listed in the sources ledger.