Can you see the northern lights in Longyearbyen in August?

Not in August 2027. The sun stays above -6 degrees every night at Longyearbyen, so there is no civil darkness.

How dark is Longyearbyen in August?

Longyearbyen averages 0.0 hours of civil night a night in August 2027, from 0 min on the 1st to 0 min on the last night.

How cloudy is Longyearbyen in August?

NASA POWER's 2001 to 2020 climatology gives Longyearbyen's 1 degree cell 82% mean cloud in August, against 76% for the whole year. It is an all-hours average, not a forecast.

What is the best night in August 2027 for aurora in Longyearbyen?

No night in August 2027 has moon-free darkness inside 10 PM to 2 AM at Longyearbyen.

Is August or September better in Longyearbyen?

By civil night times the clear share, August scores 0.0 hours at Longyearbyen and September 0.9. September comes out ahead.

Longyearbyen · August 2027

Northern lights in Longyearbyen in August 2027

Answer

Longyearbyen has no civil darkness in August 2027: the sun stays above -6 degrees on all 31 nights. SWPC notes that "It must also be dark so during the summer months at auroral latitudes, the midnight sun prevents auroral observations."

0.0 h

civil night, average night

SunCalc for 78.22, 15.65; NASA POWER; GFZ Kp

August against the rest of the year

6.2

4.5

2.7

0.0

0.9

2.8

5.8

6.2

August cloud at Longyearbyen averages 82% in NASA POWER's 2001 to 2020 record, 6 points cloudier than its yearly mean. April is Longyearbyen's clearest month at 67%. By civil night times clear sky, August scores 0.0 hours at Longyearbyen, 8th of 12. Alta, 945 km away, averages 78%, clearer by 4 points.

The sun never gets 6 degrees below the horizon at Longyearbyen in August 2027, so every night is twilight or daylight. Darkness returns in September: 5.1 hours of civil night by the 15th.

August night by night

The moon runs its cycle as usual, new on Aug 2 and Aug 31 and full on Aug 17, but with no civil night it makes no difference at Longyearbyen in August.

1
0% lit
no night
2
0% lit
no night
New
3
3% lit
no night
4
9% lit
no night
5
17% lit
no night
6
26% lit
no night
7
37% lit
no night
8
47% lit
no night
9
57% lit
no night
10
67% lit
no night
11
76% lit
no night
12
84% lit
no night
13
90% lit
no night
14
95% lit
no night
15
98% lit
no night
16
100% lit
no night
17
100% lit
no night
Full
18
98% lit
no night
19
94% lit
no night
20
88% lit
no night
21
81% lit
no night
22
72% lit
no night
23
63% lit
no night
24
52% lit
no night
25
41% lit
no night
26
30% lit
no night
27
20% lit
no night
28
11% lit
no night
29
5% lit
no night
30
1% lit
no night
31
0% lit
no night
New

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 Augusts

Quiet activity already puts the oval edge over Longyearbyen, so storm days matter more: 99 of the 930 August days from 1996 to 2025 (11%) reached Kp 5, 5th of 12 months. Longyearbyen sits at 75.3 degrees geomagnetic, poleward of SWPC's 60 to 75 degree band. The quiet oval can lie south of the town, so aurora often shows low in the southern sky, and storms push the oval farther south.

August across Svalbard and Jan Mayen

Coming from July (0.0 hours at Longyearbyen), August changes little, and the nights keep growing into September (5.1 hours on the 15th).

Darkness and moon, every night

Longyearbyen, August 2027: each night from local noon to the next noon
Night	Civil	Astronomical	Moon-free dark	Moon-free, 10 PM to 2 AM	Moon lit
Sun Aug 1	0 min	0 min	0 min	0 min	0%
Mon Aug 2	0 min	0 min	0 min	0 min	0%
Tue Aug 3	0 min	0 min	0 min	0 min	3%
Wed Aug 4	0 min	0 min	0 min	0 min	9%
Thu Aug 5	0 min	0 min	0 min	0 min	17%
Fri Aug 6	0 min	0 min	0 min	0 min	26%
Sat Aug 7	0 min	0 min	0 min	0 min	37%
Sun Aug 8	0 min	0 min	0 min	0 min	47%
Mon Aug 9	0 min	0 min	0 min	0 min	57%
Tue Aug 10	0 min	0 min	0 min	0 min	67%
Wed Aug 11	0 min	0 min	0 min	0 min	76%
Thu Aug 12	0 min	0 min	0 min	0 min	84%
Fri Aug 13	0 min	0 min	0 min	0 min	90%
Sat Aug 14	0 min	0 min	0 min	0 min	95%
Sun Aug 15	0 min	0 min	0 min	0 min	98%
Mon Aug 16	0 min	0 min	0 min	0 min	100%
Tue Aug 17	0 min	0 min	0 min	0 min	100%
Wed Aug 18	0 min	0 min	0 min	0 min	98%
Thu Aug 19	0 min	0 min	0 min	0 min	94%
Fri Aug 20	0 min	0 min	0 min	0 min	88%
Sat Aug 21	0 min	0 min	0 min	0 min	81%
Sun Aug 22	0 min	0 min	0 min	0 min	72%
Mon Aug 23	0 min	0 min	0 min	0 min	63%
Tue Aug 24	0 min	0 min	0 min	0 min	52%
Wed Aug 25	0 min	0 min	0 min	0 min	41%
Thu Aug 26	0 min	0 min	0 min	0 min	30%
Fri Aug 27	0 min	0 min	0 min	0 min	20%
Sat Aug 28	0 min	0 min	0 min	0 min	11%
Sun Aug 29	0 min	0 min	0 min	0 min	5%
Mon Aug 30	0 min	0 min	0 min	0 min	1%
Tue Aug 31	0 min	0 min	0 min	0 min	0%

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

Questions

Can you see the northern lights in Longyearbyen in August?: Not in August 2027. The sun stays above -6 degrees every night at Longyearbyen, so there is no civil darkness.
How dark is Longyearbyen in August?: Longyearbyen averages 0.0 hours of civil night a night in August 2027, from 0 min on the 1st to 0 min on the last night.
How cloudy is Longyearbyen in August?: NASA POWER's 2001 to 2020 climatology gives Longyearbyen's 1 degree cell 82% mean cloud in August, against 76% for the whole year. It is an all-hours average, not a forecast.
What is the best night in August 2027 for aurora in Longyearbyen?: No night in August 2027 has moon-free darkness inside 10 PM to 2 AM at Longyearbyen.
Is August or September better in Longyearbyen?: By civil night times the clear share, August scores 0.0 hours at Longyearbyen and September 0.9. September 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.