Where in Zealand is best for the aurora?

By geomagnetic latitude, Kalundborg at 55.6°. No town sits at 60 degrees or more, so every town needs some activity.

Which town in Zealand has the longest December night?

Kalundborg, with 15.3 hours of civil night on December 15.

Which town in Zealand has the clearest dark season?

Kalundborg, with 68% mean cloud amount in the months with at least 4 hours of civil night (NASA POWER, 2001 to 2020).

What is the best month for aurora in Zealand?

October for 5 of 8 towns, by civil night times the clear share of the sky. Each town page gives its own month.

Denmark · 9 towns

Aurora towns in Zealand

Answer

Glow tracks 9 towns in Zealand, Denmark. They sit between 55.0° at Klinteby Frihed and 55.6° at Kalundborg on the IGRF-14 dipole. The regional median, 55.3 degrees, is 0.3 degrees below the median for Denmark.

55.3°

median geomagnetic latitude

IGRF-14 dipole, SunCalc, NASA POWER

Where the towns sit

60° geomagnetic or more, no storm needed55° to 60°, G1 or lessbelow 55°, storm needed

The widest gap in the dipole ranking falls between Køge and Klinteby Frihed, 0.2 degrees. 7 neighbouring pairs sit within 0.5 degrees of each other, close enough that the order between them means little.

Of the 8 indexed towns in Zealand, 8 sit between 55 and 60 degrees, where G1 (Kp 5) or less usually brings aurora into view.

Ranked by geomagnetic latitude

Dipole latitude, highest first
Rank	Town	Value
1	Kalundborg	55.6°
2	Holbæk	55.5°
3	Roskilde	55.4°
4	Greve	55.3°
5	Slagelse	55.3°
6	Ringsted	55.2°
7	Køge	55.2°
8	Klinteby Frihed	55.0°

Ranked by December darkness

On December 15 the median town gets 15.2 hours of civil night, against 15.3 nationally. Kalundborg has the most at 15.3 hours and Greve the least at 15.2. Every town keeps some civil darkness through the June solstice.

Civil night on December 15, longest first
Rank	Town	Value
1	Kalundborg	15.3 h
2	Holbæk	15.3 h
3	Roskilde	15.3 h
4	Greve	15.2 h
5	Slagelse	15.2 h
6	Ringsted	15.2 h
7	Køge	15.2 h
8	Klinteby Frihed	15.2 h

Ranked by clear dark season

NASA POWER's 2001 to 2020 climatology puts median cloud amount in the dark months at 68%, against 70% nationally. Kalundborg is clearest at 68% and Køge cloudiest at 70%. These are all-hours averages for 1 degree cells, not forecasts.

Mean cloud amount in months with 4 hours or more of civil night, clearest first
Rank	Town	Value
1	Kalundborg	68%
2	Holbæk	68%
3	Slagelse	68%
4	Ringsted	68%
5	Klinteby Frihed	68%
6	Roskilde	70%
7	Greve	70%
8	Køge	70%

Multiplying civil night by the clear share of the sky, October comes out best for 5 of the 8 towns and September for 3. SWPC notes a tendency toward larger storms near the equinoxes, which this score does not include.

Every town

9 towns in Zealand
Town	Dipole	Storm needed	Dec 15 night	Dark-month cloud	Best month
Kalundborg	55.6°	G1 or less	15.3 h	68%	Oct
Holbæk	55.5°	G1 or less	15.3 h	68%	Oct
Roskilde	55.4°	G1 or less	15.3 h	70%	Sep
Greve	55.3°	G1 or less	15.2 h	70%	Sep
Slagelse	55.3°	G1 or less	15.2 h	68%	Oct
Ringsted	55.2°	G1 or less	15.2 h	68%	Oct
Køge	55.2°	G1 or less	15.2 h	70%	Sep
Næstved *	55.0°	G1 or less	15.2 h	68%	Oct
Klinteby Frihed	55.0°	G1 or less	15.2 h	68%	Oct

* Within 15 km of a larger town with the same rounded figures; its page points to that town. Cloud: NASA POWER mean for months with at least 4 hours of civil night.

Questions

Where in Zealand is best for the aurora?: By geomagnetic latitude, Kalundborg at 55.6°. No town sits at 60 degrees or more, so every town needs some activity.
Which town in Zealand has the longest December night?: Kalundborg, with 15.3 hours of civil night on December 15.
Which town in Zealand has the clearest dark season?: Kalundborg, with 68% mean cloud amount in the months with at least 4 hours of civil night (NASA POWER, 2001 to 2020).
What is the best month for aurora in Zealand?: October for 5 of 8 towns, by civil night times the clear share of the sky. Each town page gives its own month.

Sources and verification

GeoNames dump (CC BY 4.0)https://download.geonames.org/export/dump/
IGRF-14, NOAA NCEIhttps://www.ngdc.noaa.gov/IAGA/vmod/coeffs/igrf14coeffs.txt
NASA POWER climatologyhttps://power.larc.nasa.gov/docs/services/api/temporal/climatology/

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.