Comparison
Helsinki vs Vantaa for the northern lights
Answer
Side by side
| Figure | Helsinki | Vantaa |
|---|---|---|
| Dipole latitude | 57.7° | 57.8° |
| Kp for the oval edge overhead | Kp 5 | Kp 5 |
| Civil night, December 15 | 16.0 h | 16.1 h |
| Dark-season days | 299 | 297 |
| Nights with no civil darkness | 10 | 16 |
| Dark-month cloud, NASA POWER | 74% | 74% |
| Solar midnight, December 15 | 00:15 | 00:15 |
Helsinki sits at 57.7 degrees geomagnetic. By SWPC's rule the average oval edge is overhead at Kp 5, and aurora is usually visible on the northern horizon at G1 (Kp 5) or less. Vantaa sits at 57.8 degrees geomagnetic. By SWPC's rule the average oval edge is overhead at Kp 5, and aurora is usually visible on the northern horizon at G1 (Kp 5) or less.
Civil night month by month
On December 15 Helsinki has 16.0 hours of civil night and Vantaa 16.1. Across the 15th of each month, Helsinki is darker in 5 months and Vantaa in 2. The widest gap comes in June, when Helsinki has 0.2 more hours.
| Month | Helsinki | Vantaa | Difference |
|---|---|---|---|
| January | 15.4 h | 15.4 h | +0.0 h |
| February | 13.2 h | 13.2 h | +0.0 h |
| March | 10.7 h | 10.7 h | +0.0 h |
| April | 7.7 h | 7.6 h | +0.1 h |
| May | 4.4 h | 4.3 h | +0.1 h |
| June | 0.2 h | 0.0 h | +0.2 h |
| July | 2.9 h | 2.8 h | +0.1 h |
| August | 6.5 h | 6.4 h | +0.1 h |
| September | 9.6 h | 9.6 h | +0.0 h |
| October | 12.3 h | 12.3 h | +0.0 h |
| November | 14.7 h | 14.8 h | -0.1 h |
| December | 16.0 h | 16.1 h | -0.1 h |
Season and midnight sun
Helsinki has no civil darkness from June 16 to June 25, 10 nights in 2026, and its dark season, 4 or more evening hours of civil night, lasts 299 days. Vantaa has no civil darkness from June 13 to June 28, 16 nights in 2026, and its dark season, 4 or more evening hours of civil night, lasts 297 days.
Distance, cloud and time zones
The two towns are 15 km apart by great circle. In the dark months both average about 74% cloud in NASA POWER's 2001 to 2020 record. Helsinki's best month by civil night times clear sky is March. Vantaa'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 Helsinki and Vantaa, which carry the live OVATION cell.
Questions
- Is Helsinki or Vantaa better for the northern lights?
- Vantaa sits closer to the oval, at 57.8 degrees geomagnetic against 57.7. 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, Helsinki or Vantaa?
- Vantaa, with 16.1 hours of civil night on December 15 against 16.0 in Helsinki.
- What Kp do Helsinki and Vantaa need?
- By SWPC's rule of 66 degrees at Kp 0 and 2 degrees per step, Helsinki needs about Kp 5 and Vantaa Kp 5 for the average oval edge to sit overhead.
- When is it too light for aurora in Helsinki and Vantaa?
- Helsinki: June 16 to June 25. Vantaa: June 13 to June 28.
- Which is clearer, Helsinki or Vantaa?
- Helsinki, with 74% mean cloud in the months with 4 hours or more of civil night against 74% in Vantaa (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.