Is Uppsala or Västerås better for the northern lights?

Uppsala sits closer to the oval, at 58.5 degrees geomagnetic against 58.5. 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, Uppsala or Västerås?

Uppsala, with 16.0 hours of civil night on December 15 against 15.9 in Västerås.

What Kp do Uppsala and Västerås need?

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

When is it too light for aurora in Uppsala and Västerås?

Uppsala: never, every night has civil darkness. Västerås: never, every night has civil darkness.

Which is clearer, Uppsala or Västerås?

Uppsala, with 77% mean cloud in the months with 4 hours or more of civil night against 77% in Västerås (NASA POWER, 2001 to 2020).

Comparison

Uppsala vs Västerås for the northern lights

Answer

Uppsala sits 0.1 degrees higher on the IGRF-14 dipole, 58.5 against 58.5. By SWPC's oval-edge rule Uppsala needs about Kp 4 for the average edge to sit overhead and Västerås Kp 4. On the map Uppsala is also closer to the pole, by 0.2 degrees.

58.5° / 58.5°

dipole latitude

Side by side

Computed figures for both towns
Figure	Uppsala	Västerås
Dipole latitude	58.5°	58.5°
Kp for the oval edge overhead	Kp 4	Kp 4
Civil night, December 15	16.0 h	15.9 h
Dark-season days	301	303
Nights with no civil darkness	0	0
Dark-month cloud, NASA POWER	77%	77%
Solar midnight, December 15	23:45	23:49

Uppsala sits at 58.5 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. Västerås sits at 58.5 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.

Civil night month by month

On December 15 Uppsala has 16.0 hours of civil night and Västerås 15.9. Across the 15th of each month, Uppsala is darker in 1 months and Västerås in 4. The widest gap comes in June, when Västerås has 0.4 more hours.

Hours of civil night on the 15th of each month, 2026
Month	Uppsala	Västerås	Difference
January	15.3 h	15.3 h	+0.0 h
February	13.1 h	13.1 h	+0.0 h
March	10.7 h	10.7 h	+0.0 h
April	7.7 h	7.8 h	-0.1 h
May	4.5 h	4.6 h	-0.1 h
June	1.2 h	1.6 h	-0.4 h
July	3.2 h	3.3 h	-0.1 h
August	6.6 h	6.6 h	+0.0 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	14.7 h	+0.0 h
December	16.0 h	15.9 h	+0.1 h

Difference: Uppsala minus Västerås. Each figure links to that town's month page.

Season and midnight sun

Uppsala has some civil darkness every night of 2026, and its dark season, 4 or more evening hours of civil night, lasts 301 days. Västerås has some civil darkness every night of 2026, and its dark season, 4 or more evening hours of civil night, lasts 303 days.

Distance, cloud and time zones

The two towns are 67 km apart by great circle. In the dark months both average about 77% cloud in NASA POWER's 2001 to 2020 record. Uppsala's best month by civil night times clear sky is November. Västerås's best month by civil night times clear sky is November. Time zones: Europe/Stockholm and Europe/Stockholm.

For tonight, open the live pages for Uppsala and Västerås, which carry the live OVATION cell.

Questions

Is Uppsala or Västerås better for the northern lights?: Uppsala sits closer to the oval, at 58.5 degrees geomagnetic against 58.5. 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, Uppsala or Västerås?: Uppsala, with 16.0 hours of civil night on December 15 against 15.9 in Västerås.
What Kp do Uppsala and Västerås need?: By SWPC's rule of 66 degrees at Kp 0 and 2 degrees per step, Uppsala needs about Kp 4 and Västerås Kp 4 for the average oval edge to sit overhead.
When is it too light for aurora in Uppsala and Västerås?: Uppsala: never, every night has civil darkness. Västerås: never, every night has civil darkness.
Which is clearer, Uppsala or Västerås?: Uppsala, with 77% mean cloud in the months with 4 hours or more of civil night against 77% in Västerås (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.