Viljandi · June 2027
Northern lights in Viljandi in June 2027
Answer
June against the rest of the year
June cloud at Viljandi averages 63% in NASA POWER's 2001 to 2020 record, 8 points clearer than its yearly mean. May is Viljandi's clearest month at 56%. By civil night times clear sky, June scores 1.0 hours at Viljandi, 12th of 12. Tallinn, 129 km away, averages 61%, clearer by 2 points.
Civil night at Viljandi starts June at 3 h 35 min and reaches 2 h 55 min by June 30, 0.7 hours shorter. No night keeps the 10 PM to 2 AM window fully dark at Viljandi. The sun never reaches 18 degrees down, so Viljandi gets no astronomical night in June.
June night by night
June opens toward a new moon on Jun 4, with full moon on Jun 19, in Europe/Tallinn dates. Viljandi gets 38 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: Jun 1 (2 h 32 min), Jun 2 (2 h 30 min), Jun 3 (2 h 27 min).
- 1
11% lit
3.1 h
- 2
5% lit
3.3 h
- 3
1% lit
3.4 h
- 4
0% lit
3.4 h
- 5
2% lit
3.0 h
- 6
6% lit
2.3 h
- 7
13% lit
1.9 h
- 8
22% lit
1.7 h
- 9
33% lit
1.6 h
- 10
44% lit
1.5 h
- 11
55% lit
1.4 h
- 12
65% lit
1.3 h
- 13
75% lit
1.2 h
- 14
84% lit
1.1 h
- 15
90% lit
0.9 h
- 16
95% lit
0.6 h
- 17
99% lit
0.1 h
- 18
100% lit
0.0 h
- 19
99% lit
0.0 h
- 20
97% lit
0.0 h
- 21
93% lit
0.2 h
- 22
87% lit
0.3 h
- 23
80% lit
0.4 h
- 24
72% lit
0.5 h
- 25
63% lit
0.5 h
- 26
53% lit
0.6 h
- 27
43% lit
0.7 h
- 28
33% lit
0.8 h
- 29
23% lit
1.0 h
- 30
15% lit
1.3 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.
Activity in past Junes
Viljandi needs Kp 6 for the average oval edge to sit overhead. 29 of the 900 June days from 1996 to 2025 (3%) reached it in the GFZ Potsdam record, 7th of 12 months; storm days with Kp 5 or more made up 8%. Viljandi sits at 55.9 degrees geomagnetic. By SWPC's rule the average oval edge is overhead at Kp 6, and aurora is usually visible on the northern horizon at G1 (Kp 5) or less.
June across Estonia
No month-page town in Estonia has more civil night on June 15 than Viljandi; the national median is 2.3 hours. Coming from May (5.1 hours at Viljandi), June loses darkness, and the nights keep growing into July (4.0 hours on the 15th). The June solstice falls on June 21, 17:07 Viljandi time.
Darkness and moon, every night
| Night | Civil | Astronomical | Moon-free dark | Moon-free, 10 PM to 2 AM | Moon lit |
|---|---|---|---|---|---|
| Tue Jun 1 | 3 h 35 min | 0 min | 3 h 9 min | 2 h 32 min | 11% |
| Wed Jun 2 | 3 h 30 min | 0 min | 3 h 19 min | 2 h 30 min | 5% |
| Thu Jun 3 | 3 h 26 min | 0 min | 3 h 26 min | 2 h 27 min | 1% |
| Fri Jun 4 | 3 h 21 min | 0 min | 3 h 21 min | 2 h 25 min | 0% |
| Sat Jun 5 | 3 h 17 min | 0 min | 3 h 1 min | 2 h 6 min | 2% |
| Sun Jun 6 | 3 h 13 min | 0 min | 2 h 20 min | 1 h 27 min | 6% |
| Mon Jun 7 | 3 h 9 min | 0 min | 1 h 57 min | 1 h 6 min | 13% |
| Tue Jun 8 | 3 h 6 min | 0 min | 1 h 43 min | 54 min | 22% |
| Wed Jun 9 | 3 h 2 min | 0 min | 1 h 34 min | 46 min | 33% |
| Thu Jun 10 | 2 h 59 min | 0 min | 1 h 28 min | 41 min | 44% |
| Fri Jun 11 | 2 h 56 min | 0 min | 1 h 22 min | 37 min | 55% |
| Sat Jun 12 | 2 h 54 min | 0 min | 1 h 17 min | 32 min | 65% |
| Sun Jun 13 | 2 h 51 min | 0 min | 1 h 10 min | 27 min | 75% |
| Mon Jun 14 | 2 h 49 min | 0 min | 1 h 3 min | 20 min | 84% |
| Tue Jun 15 | 2 h 47 min | 0 min | 52 min | 10 min | 90% |
| Wed Jun 16 | 2 h 45 min | 0 min | 34 min | 0 min | 95% |
| Thu Jun 17 | 2 h 44 min | 0 min | 3 min | 0 min | 99% |
| Fri Jun 18 | 2 h 43 min | 0 min | 0 min | 0 min | 100% |
| Sat Jun 19 | 2 h 42 min | 0 min | 0 min | 0 min | 99% |
| Sun Jun 20 | 2 h 42 min | 0 min | 0 min | 0 min | 97% |
| Mon Jun 21 | 2 h 42 min | 0 min | 12 min | 12 min | 93% |
| Tue Jun 22 | 2 h 42 min | 0 min | 19 min | 19 min | 87% |
| Wed Jun 23 | 2 h 43 min | 0 min | 24 min | 24 min | 80% |
| Thu Jun 24 | 2 h 44 min | 0 min | 28 min | 28 min | 72% |
| Fri Jun 25 | 2 h 45 min | 0 min | 32 min | 32 min | 63% |
| Sat Jun 26 | 2 h 46 min | 0 min | 36 min | 36 min | 53% |
| Sun Jun 27 | 2 h 48 min | 0 min | 41 min | 41 min | 43% |
| Mon Jun 28 | 2 h 50 min | 0 min | 48 min | 48 min | 33% |
| Tue Jun 29 | 2 h 53 min | 0 min | 58 min | 58 min | 23% |
| Wed Jun 30 | 2 h 55 min | 0 min | 1 h 15 min | 1 h 15 min | 15% |
Questions
- Can you see the northern lights in Viljandi in June?
- On dark, clear nights with enough activity. 30 of 30 nights at Viljandi have civil darkness, and 3% of past June days reached Kp 6.
- How dark is Viljandi in June?
- Viljandi averages 2.9 hours of civil night a night in June 2027, from 3 h 35 min on the 1st to 2 h 55 min on the last night.
- How cloudy is Viljandi in June?
- NASA POWER's 2001 to 2020 climatology gives Viljandi's 1 degree cell 63% mean cloud in June, against 71% for the whole year. It is an all-hours average, not a forecast.
- What is the best night in June 2027 for aurora in Viljandi?
- By darkness and moon alone, Jun 1, with 2 h 32 min of moon-free darkness inside 10 PM to 2 AM at Viljandi. Activity on that date will only be known hours ahead.
- Is June or July better in Viljandi?
- By civil night times the clear share, June scores 1.0 hours at Viljandi and July 1.5. July 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.