Lappeenranta · December 2026
Northern lights in Lappeenranta in December 2026
Answer
December against the rest of the year
December cloud at Lappeenranta averages 84% in NASA POWER's 2001 to 2020 record, 8 points cloudier than its yearly mean. August is Lappeenranta's clearest month at 69%. By civil night times clear sky, December scores 2.6 hours at Lappeenranta, 5th of 12. Lahti, 136 km away, averages 85%, cloudier by 1 points.
Civil night at Lappeenranta starts December at 15 h 48 min and reaches 16 h 9 min by December 31 as the nights lengthen by 0.3 hours. SWPC's 10 PM to 2 AM window is fully dark on every night. True astronomical darkness, the sun 18 degrees down, lasts 12.5 hours on the 15th.
December night by night
December opens toward a new moon on Dec 9, with full moon on Dec 24, in Europe/Helsinki dates. Lappeenranta gets 270 hours of civil night with the moon below the horizon across the month. The best of them for moon-free darkness inside 10 PM to 2 AM: Dec 3 (4 h), Dec 4 (4 h), Dec 5 (4 h).
- 1
43% lit
8.3 h
- 2
33% lit
9.8 h
- 3
24% lit
11.4 h
- 4
16% lit
12.9 h
- 5
9% lit
14.6 h
- 6
4% lit
16.0 h
- 7
1% lit
16.0 h
- 8
0% lit
16.1 h
- 9
1% lit
16.1 h
- 10
3% lit
16.1 h
- 11
7% lit
16.1 h
- 12
13% lit
14.5 h
- 13
20% lit
12.9 h
- 14
28% lit
11.5 h
- 15
37% lit
10.0 h
- 16
47% lit
8.6 h
- 17
57% lit
7.1 h
- 18
67% lit
5.5 h
- 19
77% lit
3.9 h
- 20
86% lit
2.0 h
- 21
93% lit
0.1 h
- 22
98% lit
0.0 h
- 23
100% lit
0.0 h
- 24
99% lit
0.0 h
- 25
95% lit
0.5 h
- 26
88% lit
2.4 h
- 27
80% lit
4.3 h
- 28
70% lit
6.0 h
- 29
59% lit
7.5 h
- 30
49% lit
9.1 h
- 31
39% lit
10.6 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.
Activity in past Decembers
Lappeenranta needs Kp 4 for the average oval edge to sit overhead. 173 of the 930 December days from 1996 to 2025 (19%) reached it in the GFZ Potsdam record, one of the three quietest months for that level; storm days with Kp 5 or more made up 5%. Lappeenranta sits at 58.1 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.
December across Finland
Lappeenranta ranks 20th in Finland for civil night on December 15, behind Rovaniemi at 17.7 hours. Coming from November (14.9 hours at Lappeenranta), December adds darkness, and January brings shorter nights (15.5 hours on the 15th). The December solstice falls on December 21, 22:49 Lappeenranta time.
| Town | Civil night | Cloud |
|---|---|---|
| Rovaniemi | 17.7 h | 81% |
| Tornio | 17.5 h | 81% |
| Kemi | 17.5 h | 81% |
| Oulu | 17.3 h | 81% |
| Haukipudas | 17.3 h | 81% |
| Raahe | 17.2 h | 84% |
| Kajaani | 17.0 h | 80% |
| Ylivieska | 17.0 h | 84% |
| Kokkola | 16.9 h | 84% |
| Jakobstad | 16.9 h | 84% |
| Iisalmi | 16.8 h | 83% |
| Kuopio | 16.7 h | 85% |
| Lappeenranta | 16.2 h | 84% |
Darkness and moon, every night
| Night | Civil | Astronomical | Moon-free dark | Moon-free, 10 PM to 2 AM | Moon lit |
|---|---|---|---|---|---|
| Tue Dec 1 | 15 h 48 min | 12 h 10 min | 8 h 18 min | 2 h 21 min | 43% |
| Wed Dec 2 | 15 h 50 min | 12 h 12 min | 9 h 51 min | 3 h 53 min | 33% |
| Thu Dec 3 | 15 h 53 min | 12 h 14 min | 11 h 23 min | 4 h | 24% |
| Fri Dec 4 | 15 h 55 min | 12 h 16 min | 12 h 57 min | 4 h | 16% |
| Sat Dec 5 | 15 h 58 min | 12 h 18 min | 14 h 34 min | 4 h | 9% |
| Sun Dec 6 | 16 h | 12 h 20 min | 16 h | 4 h | 4% |
| Mon Dec 7 | 16 h 2 min | 12 h 21 min | 16 h 2 min | 4 h | 1% |
| Tue Dec 8 | 16 h 4 min | 12 h 23 min | 16 h 4 min | 4 h | 0% |
| Wed Dec 9 | 16 h 6 min | 12 h 24 min | 16 h 6 min | 4 h | 1% |
| Thu Dec 10 | 16 h 7 min | 12 h 25 min | 16 h 7 min | 4 h | 3% |
| Fri Dec 11 | 16 h 9 min | 12 h 27 min | 16 h 4 min | 4 h | 7% |
| Sat Dec 12 | 16 h 10 min | 12 h 28 min | 14 h 30 min | 4 h | 13% |
| Sun Dec 13 | 16 h 11 min | 12 h 29 min | 12 h 57 min | 4 h | 20% |
| Mon Dec 14 | 16 h 13 min | 12 h 30 min | 11 h 28 min | 4 h | 28% |
| Tue Dec 15 | 16 h 14 min | 12 h 30 min | 10 h 2 min | 3 h 52 min | 37% |
| Wed Dec 16 | 16 h 14 min | 12 h 31 min | 8 h 35 min | 2 h 25 min | 47% |
| Thu Dec 17 | 16 h 15 min | 12 h 31 min | 7 h 7 min | 55 min | 57% |
| Fri Dec 18 | 16 h 16 min | 12 h 32 min | 5 h 33 min | 0 min | 67% |
| Sat Dec 19 | 16 h 16 min | 12 h 32 min | 3 h 51 min | 0 min | 77% |
| Sun Dec 20 | 16 h 16 min | 12 h 32 min | 2 h 1 min | 0 min | 86% |
| Mon Dec 21 | 16 h 16 min | 12 h 32 min | 5 min | 0 min | 93% |
| Tue Dec 22 | 16 h 16 min | 12 h 32 min | 0 min | 0 min | 98% |
| Wed Dec 23 | 16 h 16 min | 12 h 32 min | 0 min | 0 min | 100% |
| Thu Dec 24 | 16 h 15 min | 12 h 32 min | 0 min | 0 min | 99% |
| Fri Dec 25 | 16 h 15 min | 12 h 31 min | 28 min | 0 min | 95% |
| Sat Dec 26 | 16 h 14 min | 12 h 31 min | 2 h 26 min | 0 min | 88% |
| Sun Dec 27 | 16 h 13 min | 12 h 30 min | 4 h 15 min | 0 min | 80% |
| Mon Dec 28 | 16 h 12 min | 12 h 29 min | 5 h 57 min | 0 min | 70% |
| Tue Dec 29 | 16 h 11 min | 12 h 29 min | 7 h 32 min | 1 h 35 min | 59% |
| Wed Dec 30 | 16 h 10 min | 12 h 28 min | 9 h 4 min | 3 h 9 min | 49% |
| Thu Dec 31 | 16 h 9 min | 12 h 26 min | 10 h 37 min | 4 h | 39% |
Questions
- Can you see the northern lights in Lappeenranta in December?
- On dark, clear nights with enough activity. 31 of 31 nights at Lappeenranta have civil darkness, and 19% of past December days reached Kp 4.
- How dark is Lappeenranta in December?
- Lappeenranta averages 16.1 hours of civil night a night in December 2026, from 15 h 48 min on the 1st to 16 h 9 min on the last night.
- How cloudy is Lappeenranta in December?
- NASA POWER's 2001 to 2020 climatology gives Lappeenranta's 1 degree cell 84% mean cloud in December, against 76% for the whole year. It is an all-hours average, not a forecast.
- What is the best night in December 2026 for aurora in Lappeenranta?
- By darkness and moon alone, Dec 3, with 4 h of moon-free darkness inside 10 PM to 2 AM at Lappeenranta. Activity on that date will only be known hours ahead.
- Is December or January better in Lappeenranta?
- By civil night times the clear share, December scores 2.6 hours at Lappeenranta and January 3.3. January comes out ahead.
Sources and verification
- SunCalchttps://github.com/mourner/suncalc
- NASA POWER climatologyhttps://power.larc.nasa.gov/docs/services/api/temporal/climatology/
- GFZ Potsdam Kp indexhttps://kp.gfz.de/en/data
- 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.