Jönköping, Sweden
Northern lights in Nässjö
Answer
Tonight
Waiting on darkness
It is not civil-dark yet. The next dusk is listed below.
Observed 11:55 UTC, forecast 13:26 UTC, 91 min lead
Clock times in Europe/Stockholm
Storm level needed
Nässjö sits at 57.65N 14.70E in Jönköping, Sweden. The IGRF-14 centered dipole puts Nässjö at 56.9 degrees geomagnetic latitude, 0.8 degrees farther from the magnetic pole than its map latitude suggests. Nässjö sits at 56.9 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.
"aurora is commonly visible at high latitudes (northern Michigan and Maine)"
The nearest other Glow towns are Jönköping (35 km), Värnamo (65 km), Växjö (86 km). Jönköping sits 0.2 degrees higher on the dipole and needs the same Kp.
Approximate: SWPC calls its Kp to latitude rule an average, and a centered dipole can differ by a degree from fuller field models. How the storm level is matched
The year in darkness
Every night of 2026 at Nässjö has some civil darkness; the shortest month sample still has 3.3 hours. Glow's dark season, at least 4 hours of civil night between 18:00 and 06:00, runs from July 11 to May 31 across New Year, 325 days in 2026. Nässjö's longest night of the year, Dec 20, has 15 h 37 min of civil night.
Solar midnight at Nässjö, when the sun is lowest, falls at 23:56 on local clocks on December 15 and 01:01 on June 15. That is 4 min before midnight in December and 1 h 1 min after midnight in June, the gap set by daylight saving and the equation of time. So at Nässjö the darkest hour sits near the middle of SWPC's 10 PM to 2 AM window in winter.
Month by month
| Month | Night | Civil | Cloud | Clear dark | |
|---|---|---|---|---|---|
| Jan | 15.0 h | 11.8 h | 81% | 2.8 h | |
| Feb | 13.0 h | 10.0 h | 79% | 2.7 h | |
| Mar | 10.8 h | 7.6 h | 72% | 3.0 h | |
| Apr | 8.1 h | 3.8 h | 63% | 3.0 h | |
| May | 5.3 h | 0.0 h | 65% | 1.9 h | |
| Jun | 3.3 h | 0.0 h | 66% | 1.1 h | |
| Jul | 4.3 h | 0.0 h | 67% | 1.4 h | |
| Aug | 7.0 h | 0.5 h | 67% | 2.3 h | |
| Sep | 9.8 h | 6.4 h | 68% | 3.1 h | |
| Oct | 12.2 h | 9.2 h | 73% | 3.3 hbest | |
| Nov | 14.4 h | 11.3 h | 78% | 3.2 h | |
| Dec | 15.6 h | 12.3 h | 81% | 3.0 h |
By the 15th-of-the-month sample, December is the darkest month at Nässjö with 15.6 hours of civil night and June the lightest at 3.3. Across the year Nässjö gets 3,607 hours of civil night. Astronomical night at Nässjö, the sun 18 degrees or more below the horizon, lasts 12.3 hours on December 15.
NASA POWER's 2001 to 2020 all-hours climatology puts mean cloud amount for the 1 degree cell around Nässjö at 72% across the year, from 63% in April to 81% in January. In the months with at least 4 hours of civil night Nässjö averages 72%, against a median of 75% for Glow towns in Sweden.
Multiplying civil night by the clear share of the sky gives October the best score, 3.3 hours, ahead of November at 3.2. Nässjö's equinox months score 3.0 in March and 3.1 in September, the weeks SWPC links with larger storms.
Kp history
From 1996 to 2025, the GFZ Potsdam record shows a 3-hour Kp of 5 or more, the level that puts the average oval edge over Nässjö, on 10% of days. At Nässjö's level the share runs from 5% in December to 14% in September, while storm days with Kp 5 or more made up 10%.
Share of UTC days in each calendar month whose highest 3-hour Kp reached Kp 5. Kp history by year
Moon, next 30 nights
Over the 30 nights from Oct 2, the new moon falls on Oct 10 and the full moon on Oct 26, in Europe/Stockholm dates. 15 of the 30 nights at Nässjö have at least 2 moon-free dark hours inside 10 PM to 2 AM, and Oct 6 has the most at 4 h. Tonight Nässjö has 11 h 12 min of civil night, 1 h 17 min of it with the moon down.
- 2
57% lit
1.3 h
- 3
46% lit
2.7 h
- 4
35% lit
4.4 h
- 5
25% lit
6.1 h
- 6
16% lit
7.7 h
- 7
8% lit
9.3 h
- 8
3% lit
10.8 h
- 9
1% lit
11.8 h
- 10
0% lit
11.8 h
- 11
2% lit
11.9 h
- 12
5% lit
12.0 h
- 13
11% lit
12.1 h
- 14
17% lit
12.2 h
- 15
25% lit
12.1 h
- 16
34% lit
11.3 h
- 17
43% lit
10.1 h
- 18
52% lit
8.8 h
- 19
62% lit
7.4 h
- 20
71% lit
6.0 h
- 21
80% lit
4.6 h
- 22
87% lit
3.2 h
- 23
94% lit
1.8 h
- 24
98% lit
0.3 h
- 25
100% lit
0.0 h
- 26
99% lit
0.0 h
- 27
95% lit
0.0 h
- 28
89% lit
0.0 h
- 29
81% lit
0.3 h
- 30
71% lit
1.6 h
- 31
60% lit
3.3 h
Each cell is the night that starts on that date. Hours are civil-dark time with the moon below the horizon; the green rule scales with them. Green outline: new moon. Bone outline: full moon.
Within Sweden
Among the 3 Glow towns in Jönköping, Nässjö ranks 2nd by dipole latitude against a regional median of 56.9 degrees; Jönköping sits highest at 57.1. Among the 74 Glow towns in Sweden, Nässjö ranks 54th by dipole latitude against a national median of 57.9 degrees; Kiruna sits highest at 65.7. On December 15 Nässjö gets 15.6 hours of civil night, 46th longest of 74 in Sweden, where the median is 15.8.
Questions
- Can you see the northern lights in Nässjö?
- Nässjö sits at 56.9 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. Clear, dark sky over Nässjö still decides it.
- When is it dark enough in Nässjö?
- Every night at Nässjö has civil darkness. Tonight has 11 h 12 min, and December 15 has 15.6 hours.
- What is the best month for aurora in Nässjö?
- October, by civil night at Nässjö times the clear share of the sky from NASA POWER's 2001 to 2020 average.
- How cloudy is Nässjö in the dark months?
- About 72% mean cloud amount over Nässjö in the months with at least 4 hours of civil night, from NASA POWER's 2001 to 2020 all-hours climatology.
- How often is activity high enough for Nässjö?
- A 3-hour Kp of 5 or more, the level that puts the average oval edge overhead, occurred on 10% of days from 1996 to 2025 in the GFZ Potsdam record.
Nearby and related
Nearest Glow towns
Nässjö by month
Region and comparisons