Is Hafnarfjörður or Reykjanesbær better for the northern lights?

Reykjanesbær sits closer to the oval, at 68.8 degrees geomagnetic against 68.7. 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, Hafnarfjörður or Reykjanesbær?

Hafnarfjörður, with 17.0 hours of civil night on December 15 against 17.0 in Reykjanesbær.

What Kp do Hafnarfjörður and Reykjanesbær need?

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

When is it too light for aurora in Hafnarfjörður and Reykjanesbær?

Hafnarfjörður: May 17 to July 25. Reykjanesbær: May 17 to July 24.

Which is clearer, Hafnarfjörður or Reykjanesbær?

Hafnarfjörður, with 79% mean cloud in the months with 4 hours or more of civil night against 83% in Reykjanesbær (NASA POWER, 2001 to 2020).

Comparison

Hafnarfjörður vs Reykjanesbær for the northern lights

Answer

Reykjanesbær sits 0.0 degrees higher on the IGRF-14 dipole, 68.8 against 68.7. By SWPC's oval-edge rule Reykjanesbær needs about Kp 0 for the average edge to sit overhead and Hafnarfjörður Kp 0. That reverses the map, where Hafnarfjörður is 0.1 degrees closer to the pole.

68.7° / 68.8°

dipole latitude

Side by side

Computed figures for both towns
Figure	Hafnarfjörður	Reykjanesbær
Dipole latitude	68.7°	68.8°
Kp for the oval edge overhead	Kp 0	Kp 0
Civil night, December 15	17.0 h	17.0 h
Dark-season days	270	271
Nights with no civil darkness	70	69
Dark-month cloud, NASA POWER	79%	83%
Solar midnight, December 15	01:23	01:25

Hafnarfjörður sits at 68.7 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 0. Reykjanesbær sits at 68.8 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 0.

Civil night month by month

On December 15 Hafnarfjörður has 17.0 hours of civil night and Reykjanesbær 17.0. Across the 15th of each month, Hafnarfjörður is darker in 1 months and Reykjanesbær in 1. The widest gap comes in May, when Reykjanesbær has 0.1 more hours.

Hours of civil night on the 15th of each month, 2026
Month	Hafnarfjörður	Reykjanesbær	Difference
January	16.1 h	16.1 h	+0.0 h
February	13.4 h	13.4 h	+0.0 h
March	10.5 h	10.5 h	+0.0 h
April	6.8 h	6.8 h	+0.0 h
May	1.4 h	1.5 h	-0.1 h
June	0.0 h	0.0 h	+0.0 h
July	0.0 h	0.0 h	+0.0 h
August	5.3 h	5.3 h	+0.0 h
September	9.2 h	9.2 h	+0.0 h
October	12.5 h	12.4 h	+0.1 h
November	15.3 h	15.3 h	+0.0 h
December	17.0 h	17.0 h	+0.0 h

Difference: Hafnarfjörður minus Reykjanesbær. Each figure links to that town's month page.

Season and midnight sun

Hafnarfjörður has no civil darkness from May 17 to July 25, 70 nights in 2026, and its dark season, 4 or more evening hours of civil night, lasts 270 days. Reykjanesbær has no civil darkness from May 17 to July 24, 69 nights in 2026, and its dark season, 4 or more evening hours of civil night, lasts 271 days.

Distance, cloud and time zones

The two towns are 31 km apart by great circle. In the dark months Hafnarfjörður averages 79% cloud and Reykjanesbær 83%, from NASA POWER's 2001 to 2020 record. Hafnarfjörður's best month by civil night times clear sky is December. Reykjanesbær's best month by civil night times clear sky is December. Time zones: Atlantic/Reykjavik and Atlantic/Reykjavik.

For tonight, open the live pages for Hafnarfjörður and Reykjanesbær, which carry the live OVATION cell.

Questions

Is Hafnarfjörður or Reykjanesbær better for the northern lights?: Reykjanesbær sits closer to the oval, at 68.8 degrees geomagnetic against 68.7. 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, Hafnarfjörður or Reykjanesbær?: Hafnarfjörður, with 17.0 hours of civil night on December 15 against 17.0 in Reykjanesbær.
What Kp do Hafnarfjörður and Reykjanesbær need?: By SWPC's rule of 66 degrees at Kp 0 and 2 degrees per step, Hafnarfjörður needs about Kp 0 and Reykjanesbær Kp 0 for the average oval edge to sit overhead.
When is it too light for aurora in Hafnarfjörður and Reykjanesbær?: Hafnarfjörður: May 17 to July 25. Reykjanesbær: May 17 to July 24.
Which is clearer, Hafnarfjörður or Reykjanesbær?: Hafnarfjörður, with 79% mean cloud in the months with 4 hours or more of civil night against 83% in Reykjanesbær (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.