Is Severodvinsk or Kostomuksha better for the northern lights?

Kostomuksha sits closer to the oval, at 61.1 degrees geomagnetic against 59.9. 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, Severodvinsk or Kostomuksha?

Severodvinsk, with 17.1 hours of civil night on December 15 against 17.1 in Kostomuksha.

What Kp do Severodvinsk and Kostomuksha need?

By SWPC's rule of 66 degrees at Kp 0 and 2 degrees per step, Severodvinsk needs about Kp 4 and Kostomuksha Kp 3 for the average oval edge to sit overhead.

When is it too light for aurora in Severodvinsk and Kostomuksha?

Severodvinsk: May 15 to July 27. Kostomuksha: May 15 to July 27.

Which is clearer, Severodvinsk or Kostomuksha?

Kostomuksha, with 78% mean cloud in the months with 4 hours or more of civil night against 80% in Severodvinsk (NASA POWER, 2001 to 2020).

Comparison

Severodvinsk vs Kostomuksha for the northern lights

Answer

Kostomuksha sits 1.2 degrees higher on the IGRF-14 dipole, 61.1 against 59.9. By SWPC's oval-edge rule Kostomuksha needs about Kp 3 for the average edge to sit overhead and Severodvinsk Kp 4. On the map Kostomuksha is also closer to the pole, by 0.0 degrees.

59.9° / 61.1°

dipole latitude

Side by side

Computed figures for both towns
Figure	Severodvinsk	Kostomuksha
Dipole latitude	59.9°	61.1°
Kp for the oval edge overhead	Kp 4	Kp 3
Civil night, December 15	17.1 h	17.1 h
Dark-season days	267	267
Nights with no civil darkness	74	74
Dark-month cloud, NASA POWER	80%	78%
Solar midnight, December 15	00:16	00:53

Severodvinsk sits at 59.9 degrees geomagnetic. By SWPC's rule the average oval edge is overhead at Kp 4, and aurora is usually visible on the northern horizon at G1 (Kp 5) or less. Kostomuksha sits at 61.1 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 Severodvinsk has 17.1 hours of civil night and Kostomuksha 17.1. Across the 15th of each month, Severodvinsk is darker in 0 months and Kostomuksha in 0. The widest gap comes in January, when Severodvinsk has 0.0 more hours.

Hours of civil night on the 15th of each month, 2026
Month	Severodvinsk	Kostomuksha	Difference
January	16.2 h	16.2 h	+0.0 h
February	13.5 h	13.5 h	+0.0 h
March	10.5 h	10.5 h	+0.0 h
April	6.7 h	6.7 h	+0.0 h
May	0.0 h	0.0 h	+0.0 h
June	0.0 h	0.0 h	+0.0 h
July	0.0 h	0.0 h	+0.0 h
August	5.1 h	5.1 h	+0.0 h
September	9.2 h	9.2 h	+0.0 h
October	12.5 h	12.5 h	+0.0 h
November	15.4 h	15.4 h	+0.0 h
December	17.1 h	17.1 h	+0.0 h

Difference: Severodvinsk minus Kostomuksha. Each figure links to that town's month page.

Season and midnight sun

Severodvinsk has no civil darkness from May 15 to July 27, 74 nights in 2026, and its dark season, 4 or more evening hours of civil night, lasts 267 days. Kostomuksha has no civil darkness from May 15 to July 27, 74 nights in 2026, and its dark season, 4 or more evening hours of civil night, lasts 267 days.

Distance, cloud and time zones

The two towns are 442 km apart by great circle. In the dark months both average about 79% cloud in NASA POWER's 2001 to 2020 record. Severodvinsk's best month by civil night times clear sky is January. Kostomuksha's best month by civil night times clear sky is January. Time zones: Europe/Moscow and Europe/Moscow.

For tonight, open the live pages for Severodvinsk and Kostomuksha, which carry the live OVATION cell.

Questions

Is Severodvinsk or Kostomuksha better for the northern lights?: Kostomuksha sits closer to the oval, at 61.1 degrees geomagnetic against 59.9. 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, Severodvinsk or Kostomuksha?: Severodvinsk, with 17.1 hours of civil night on December 15 against 17.1 in Kostomuksha.
What Kp do Severodvinsk and Kostomuksha need?: By SWPC's rule of 66 degrees at Kp 0 and 2 degrees per step, Severodvinsk needs about Kp 4 and Kostomuksha Kp 3 for the average oval edge to sit overhead.
When is it too light for aurora in Severodvinsk and Kostomuksha?: Severodvinsk: May 15 to July 27. Kostomuksha: May 15 to July 27.
Which is clearer, Severodvinsk or Kostomuksha?: Kostomuksha, with 78% mean cloud in the months with 4 hours or more of civil night against 80% in Severodvinsk (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.