Can you see the northern lights in Kostomuksha in December?

On dark, clear nights with enough activity. 31 of 31 nights at Kostomuksha have civil darkness, and 43% of past December days reached Kp 3.

How dark is Kostomuksha in December?

Kostomuksha averages 17.0 hours of civil night a night in December 2026, from 16 h 34 min on the 1st to 17 h on the last night.

How cloudy is Kostomuksha in December?

NASA POWER's 2001 to 2020 climatology gives Kostomuksha's 1 degree cell 81% 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 Kostomuksha?

By darkness and moon alone, Dec 2, with 4 h of moon-free darkness inside 10 PM to 2 AM at Kostomuksha. Activity on that date will only be known hours ahead.

Is December or January better in Kostomuksha?

By civil night times the clear share, December scores 3.2 hours at Kostomuksha and January 3.6. January comes out ahead.

Kostomuksha · December 2026

Northern lights in Kostomuksha in December 2026

Answer

December gives Kostomuksha 17.1 hours of civil night on the 15th, the darkest month of its year, under 81% mean cloud. 43% of December days since 1996 reached Kp 3, enough for the oval edge to reach Kostomuksha.

17.0 h

civil night, average night

SunCalc for 64.57, 30.58; NASA POWER; GFZ Kp

December against the rest of the year

3.6

3.0

2.8

1.9

0.0

1.5

2.4

1.8

3.2

December cloud at Kostomuksha averages 81% in NASA POWER's 2001 to 2020 record, 5 points cloudier than its yearly mean. June is Kostomuksha's clearest month at 70%. By civil night times clear sky, December scores 3.2 hours at Kostomuksha, 2nd of 12. Kajaani, 142 km away, averages 80%, clearer by 1 points.

Civil night at Kostomuksha starts December at 16 h 34 min and reaches 17 h by December 31 as the nights lengthen by 0.4 hours. SWPC's 10 PM to 2 AM window is fully dark on every night. True astronomical darkness, the sun 18 degrees down, lasts 12.8 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/Moscow dates. Kostomuksha gets 284 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 2 (4 h), Dec 3 (4 h), Dec 4 (4 h).

1
43% lit
8.6 h
2
33% lit
10.3 h
3
24% lit
12.0 h
4
16% lit
13.8 h
5
9% lit
15.6 h
6
5% lit
16.8 h
7
1% lit
16.9 h
8
0% lit
16.9 h
9
1% lit
16.9 h
New
10
3% lit
17.0 h
11
7% lit
17.0 h
12
13% lit
15.8 h
13
20% lit
13.9 h
14
28% lit
12.3 h
15
37% lit
10.7 h
16
46% lit
9.1 h
17
57% lit
7.5 h
18
67% lit
5.8 h
19
77% lit
3.9 h
20
86% lit
1.7 h
21
93% lit
0.0 h
22
98% lit
0.0 h
23
100% lit
0.0 h
24
99% lit
0.0 h
Full
25
95% lit
0.0 h
26
89% lit
2.4 h
27
80% lit
4.4 h
28
70% lit
6.3 h
29
60% lit
8.0 h
30
49% lit
9.7 h
31
39% lit
11.4 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

Kostomuksha needs Kp 3 for the average oval edge to sit overhead. 404 of the 930 December days from 1996 to 2025 (43%) 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%. Kostomuksha sits at 61.1 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 3.

December across Russia

Kostomuksha ranks 19th in Russia for civil night on December 15, behind Talnakh at 19.1 hours. Coming from November (15.4 hours at Kostomuksha), December adds darkness, and January brings shorter nights (16.2 hours on the 15th). The December solstice falls on December 21, 23:49 Kostomuksha time.

Civil night on December 15 and December cloud, month-page towns in Russia
Town	Civil night	Cloud
Talnakh	19.1 h	58%
Zapolyarnyy	19.1 h	86%
Nikel	19.1 h	86%
Norilsk	19.0 h	58%
Kayyerkan	19.0 h	59%
Dudinka	19.0 h	59%
Severomorsk	18.9 h	85%
Murmansk	18.8 h	84%
Olenegorsk	18.4 h	84%
Monchegorsk	18.3 h	80%
Apatity	18.2 h	80%
Narian-Mar	18.2 h	79%
Kostomuksha	17.1 h	81%

Darkness and moon, every night

Kostomuksha, December 2026: each night from local noon to the next noon
Night	Civil	Astronomical	Moon-free dark	Moon-free, 10 PM to 2 AM	Moon lit
Tue Dec 1	16 h 34 min	12 h 23 min	8 h 37 min	3 h 8 min	43%
Wed Dec 2	16 h 37 min	12 h 26 min	10 h 19 min	4 h	33%
Thu Dec 3	16 h 41 min	12 h 28 min	12 h 1 min	4 h	24%
Fri Dec 4	16 h 44 min	12 h 30 min	13 h 45 min	4 h	16%
Sat Dec 5	16 h 46 min	12 h 32 min	15 h 38 min	4 h	9%
Sun Dec 6	16 h 49 min	12 h 34 min	16 h 49 min	4 h	5%
Mon Dec 7	16 h 52 min	12 h 36 min	16 h 52 min	4 h	1%
Tue Dec 8	16 h 54 min	12 h 38 min	16 h 54 min	4 h	0%
Wed Dec 9	16 h 57 min	12 h 40 min	16 h 57 min	4 h	1%
Thu Dec 10	16 h 59 min	12 h 41 min	16 h 59 min	4 h	3%
Fri Dec 11	17 h 1 min	12 h 43 min	17 h 1 min	4 h	7%
Sat Dec 12	17 h 2 min	12 h 44 min	15 h 49 min	4 h	13%
Sun Dec 13	17 h 4 min	12 h 45 min	13 h 56 min	4 h	20%
Mon Dec 14	17 h 5 min	12 h 46 min	12 h 15 min	4 h	28%
Tue Dec 15	17 h 7 min	12 h 47 min	10 h 39 min	3 h 13 min	37%
Wed Dec 16	17 h 8 min	12 h 48 min	9 h 5 min	1 h 37 min	46%
Thu Dec 17	17 h 8 min	12 h 48 min	7 h 28 min	0 min	57%
Fri Dec 18	17 h 9 min	12 h 49 min	5 h 45 min	0 min	67%
Sat Dec 19	17 h 10 min	12 h 49 min	3 h 52 min	0 min	77%
Sun Dec 20	17 h 10 min	12 h 49 min	1 h 40 min	0 min	86%
Mon Dec 21	17 h 10 min	12 h 49 min	0 min	0 min	93%
Tue Dec 22	17 h 10 min	12 h 49 min	0 min	0 min	98%
Wed Dec 23	17 h 10 min	12 h 49 min	0 min	0 min	100%
Thu Dec 24	17 h 9 min	12 h 49 min	0 min	0 min	99%
Fri Dec 25	17 h 8 min	12 h 48 min	0 min	0 min	95%
Sat Dec 26	17 h 7 min	12 h 48 min	2 h 22 min	0 min	89%
Sun Dec 27	17 h 6 min	12 h 47 min	4 h 25 min	0 min	80%
Mon Dec 28	17 h 5 min	12 h 46 min	6 h 16 min	43 min	70%
Tue Dec 29	17 h 4 min	12 h 45 min	8 h	2 h 28 min	60%
Wed Dec 30	17 h 2 min	12 h 44 min	9 h 41 min	4 h	49%
Thu Dec 31	17 h	12 h 43 min	11 h 23 min	4 h	39%

Moon lit: SunCalc illuminated fraction at the middle of the 10 PM to 2 AM window.

Questions

Can you see the northern lights in Kostomuksha in December?: On dark, clear nights with enough activity. 31 of 31 nights at Kostomuksha have civil darkness, and 43% of past December days reached Kp 3.
How dark is Kostomuksha in December?: Kostomuksha averages 17.0 hours of civil night a night in December 2026, from 16 h 34 min on the 1st to 17 h on the last night.
How cloudy is Kostomuksha in December?: NASA POWER's 2001 to 2020 climatology gives Kostomuksha's 1 degree cell 81% 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 Kostomuksha?: By darkness and moon alone, Dec 2, with 4 h of moon-free darkness inside 10 PM to 2 AM at Kostomuksha. Activity on that date will only be known hours ahead.
Is December or January better in Kostomuksha?: By civil night times the clear share, December scores 3.2 hours at Kostomuksha and January 3.6. 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.