Can you see the northern lights in Fort William in December?

On dark, clear nights with enough activity. 31 of 31 nights at Fort William have civil darkness, and 19% of past December days reached Kp 4.

How dark is Fort William in December?

Fort William averages 15.4 hours of civil night a night in December 2026, from 15 h 5 min on the 1st to 15 h 22 min on the last night.

How cloudy is Fort William in December?

NASA POWER's 2001 to 2020 climatology gives Fort William's 1 degree cell 80% mean cloud in December, against 80% for the whole year. It is an all-hours average, not a forecast.

What is the best night in December 2026 for aurora in Fort William?

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

Is December or January better in Fort William?

By civil night times the clear share, December scores 3.1 hours at Fort William and January 2.5. December comes out ahead.

Fort William · December 2026

Northern lights in Fort William in December 2026

Answer

December gives Fort William 15.4 hours of civil night on the 15th, the darkest month of its year, under 80% mean cloud. 19% of December days since 1996 reached Kp 4, enough for the oval edge to reach Fort William.

15.4 h

civil night, average night

SunCalc for 56.82, -5.11; NASA POWER; GFZ Kp

December against the rest of the year

2.5

2.3

2.0

1.3

0.6

0.8

1.3

2.1

2.6

2.7

3.1

December cloud at Fort William averages 80% in NASA POWER's 2001 to 2020 record, close to its yearly mean of 80%. April is Fort William's clearest month at 76%. That makes December the best month of Fort William's year by civil night times clear sky, 3.1 hours. Glasgow, 118 km away, averages 78%, clearer by 2 points.

Civil night at Fort William starts December at 15 h 5 min and reaches 15 h 22 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 12.2 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/London dates. Fort William gets 257 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
42% lit
8.1 h
2
32% lit
9.6 h
3
23% lit
10.9 h
4
15% lit
12.3 h
5
9% lit
13.8 h
6
4% lit
15.2 h
7
1% lit
15.3 h
8
0% lit
15.3 h
9
1% lit
15.3 h
New
10
4% lit
15.3 h
11
8% lit
14.7 h
12
13% lit
13.3 h
13
21% lit
12.0 h
14
29% lit
10.7 h
15
38% lit
9.3 h
16
48% lit
8.0 h
17
58% lit
6.7 h
18
68% lit
5.2 h
19
78% lit
3.7 h
20
87% lit
2.1 h
21
94% lit
0.5 h
22
98% lit
0.0 h
23
100% lit
0.0 h
24
99% lit
0.0 h
Full
25
94% lit
0.9 h
26
88% lit
2.6 h
27
79% lit
4.3 h
28
69% lit
5.8 h
29
58% lit
7.2 h
30
48% lit
8.6 h
31
38% lit
10.0 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

Fort William 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%. Fort William sits at 59.3 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 United Kingdom

Fort William ranks 3rd in United Kingdom for civil night on December 15, behind Isle of Lewis at 15.7 hours. Coming from November (14.3 hours at Fort William), December adds darkness, and January brings shorter nights (14.9 hours on the 15th). The December solstice falls on December 21, 20:49 Fort William time.

Civil night on December 15 and December cloud, month-page towns in United Kingdom
Town	Civil night	Cloud
Isle of Lewis	15.7 h	89%
Aberdeen	15.5 h	78%
Fort William	15.4 h	80%
Dundee	15.4 h	82%
Glasgow	15.3 h	78%
Edinburgh	15.3 h	77%
Newcastle upon Tyne	15.2 h	77%
Belfast	15.1 h	80%
Sunderland	15.1 h	77%
Middlesbrough	15.1 h	77%
Manchester, England	15.0 h	82%
Leeds	15.0 h	72%

Darkness and moon, every night

Fort William, 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	15 h 5 min	11 h 56 min	8 h 7 min	2 h 45 min	42%
Wed Dec 2	15 h 8 min	11 h 58 min	9 h 33 min	4 h	32%
Thu Dec 3	15 h 10 min	12 h	10 h 57 min	4 h	23%
Fri Dec 4	15 h 12 min	12 h 1 min	12 h 21 min	4 h	15%
Sat Dec 5	15 h 13 min	12 h 3 min	13 h 47 min	4 h	9%
Sun Dec 6	15 h 15 min	12 h 4 min	15 h 11 min	4 h	4%
Mon Dec 7	15 h 17 min	12 h 6 min	15 h 17 min	4 h	1%
Tue Dec 8	15 h 18 min	12 h 7 min	15 h 18 min	4 h	0%
Wed Dec 9	15 h 20 min	12 h 8 min	15 h 20 min	4 h	1%
Thu Dec 10	15 h 21 min	12 h 9 min	15 h 21 min	4 h	4%
Fri Dec 11	15 h 22 min	12 h 10 min	14 h 39 min	4 h	8%
Sat Dec 12	15 h 23 min	12 h 11 min	13 h 20 min	4 h	13%
Sun Dec 13	15 h 24 min	12 h 12 min	12 h	4 h	21%
Mon Dec 14	15 h 25 min	12 h 12 min	10 h 40 min	4 h	29%
Tue Dec 15	15 h 26 min	12 h 13 min	9 h 21 min	3 h 22 min	38%
Wed Dec 16	15 h 27 min	12 h 14 min	8 h 2 min	2 h 2 min	48%
Thu Dec 17	15 h 27 min	12 h 14 min	6 h 40 min	40 min	58%
Fri Dec 18	15 h 28 min	12 h 14 min	5 h 14 min	0 min	68%
Sat Dec 19	15 h 28 min	12 h 15 min	3 h 42 min	0 min	78%
Sun Dec 20	15 h 28 min	12 h 15 min	2 h 4 min	0 min	87%
Mon Dec 21	15 h 28 min	12 h 15 min	27 min	0 min	94%
Tue Dec 22	15 h 28 min	12 h 15 min	0 min	0 min	98%
Wed Dec 23	15 h 28 min	12 h 15 min	0 min	0 min	100%
Thu Dec 24	15 h 28 min	12 h 14 min	0 min	0 min	99%
Fri Dec 25	15 h 27 min	12 h 14 min	54 min	0 min	94%
Sat Dec 26	15 h 27 min	12 h 13 min	2 h 37 min	0 min	88%
Sun Dec 27	15 h 26 min	12 h 13 min	4 h 15 min	0 min	79%
Mon Dec 28	15 h 25 min	12 h 12 min	5 h 47 min	26 min	69%
Tue Dec 29	15 h 24 min	12 h 12 min	7 h 14 min	1 h 54 min	58%
Wed Dec 30	15 h 23 min	12 h 11 min	8 h 38 min	3 h 20 min	48%
Thu Dec 31	15 h 22 min	12 h 10 min	10 h 2 min	4 h	38%

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

Questions

Can you see the northern lights in Fort William in December?: On dark, clear nights with enough activity. 31 of 31 nights at Fort William have civil darkness, and 19% of past December days reached Kp 4.
How dark is Fort William in December?: Fort William averages 15.4 hours of civil night a night in December 2026, from 15 h 5 min on the 1st to 15 h 22 min on the last night.
How cloudy is Fort William in December?: NASA POWER's 2001 to 2020 climatology gives Fort William's 1 degree cell 80% mean cloud in December, against 80% for the whole year. It is an all-hours average, not a forecast.
What is the best night in December 2026 for aurora in Fort William?: By darkness and moon alone, Dec 2, with 4 h of moon-free darkness inside 10 PM to 2 AM at Fort William. Activity on that date will only be known hours ahead.
Is December or January better in Fort William?: By civil night times the clear share, December scores 3.1 hours at Fort William and January 2.5. December 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.