Canterbury, New Zealand
Southern lights in Rolleston
Answer
Tonight
Darkness window open
Civil darkness has begun.
Observed 11:49 UTC, forecast 13:20 UTC, 91 min lead
Clock times in Pacific/Auckland
Storm level needed
Rolleston sits at 43.58S 172.38E in Canterbury, New Zealand. The IGRF-14 centered dipole puts Rolleston at 46.8 degrees geomagnetic latitude, 3.2 degrees closer to the magnetic pole than its map latitude suggests. Rolleston sits at 46.8 degrees geomagnetic. The lowest NOAA storm level whose typical viewing latitude reaches it is G4 (Kp = 8, including a 9-). Even Kp 9 does not put the average oval edge overhead by SWPC's rule.
"aurora has been seen as low as Alabama and northern California (typically 45° geomagnetic lat.)"
The nearest other Glow towns are Christchurch (21 km), Rangiora (35 km), Ashburton (63 km). Christchurch sits 0.1 degrees lower on the dipole and needs the same Kp.
Approximate: SWPC calls its Kp to latitude rule an average, and a centered dipole can differ by a degree from fuller field models. How the storm level is matched
The year in darkness
Every night of 2026 at Rolleston has some civil darkness; the shortest month sample still has 7.3 hours. Every evening of the year at Rolleston clears Glow's dark-season bar of 4 hours of civil night between 18:00 and 06:00. Rolleston's longest night of the year, Jun 20, has 13 h 53 min of civil night.
Solar midnight at Rolleston, when the sun is lowest, falls at 01:25 on local clocks on December 15 and 00:31 on June 15. That is 1 h 25 min after midnight in December and 31 min after midnight in June, the gap set by daylight saving and the equation of time. So at Rolleston the darkest hour sits late in SWPC's 10 PM to 2 AM window.
Month by month
| Month | Night | Civil | Cloud | Clear dark | |
|---|---|---|---|---|---|
| Jan | 7.7 h | 4.5 h | 69% | 2.4 h | |
| Feb | 9.1 h | 6.5 h | 64% | 3.3 h | |
| Mar | 10.6 h | 8.3 h | 65% | 3.7 h | |
| Apr | 12.1 h | 9.8 h | 66% | 4.1 h | |
| May | 13.3 h | 10.9 h | 65% | 4.7 h | |
| Jun | 13.8 h | 11.5 h | 65% | 4.9 h | |
| Jul | 13.6 h | 11.3 h | 63% | 5.0 hbest | |
| Aug | 12.6 h | 10.3 h | 66% | 4.3 h | |
| Sep | 11.2 h | 8.9 h | 66% | 3.8 h | |
| Oct | 9.7 h | 7.2 h | 67% | 3.2 h | |
| Nov | 8.1 h | 5.2 h | 68% | 2.6 h | |
| Dec | 7.3 h | 3.7 h | 71% | 2.1 h |
By the 15th-of-the-month sample, June is the darkest month at Rolleston with 13.9 hours of civil night and December the lightest at 7.3. Across the year Rolleston gets 3,922 hours of civil night. Astronomical night at Rolleston, the sun 18 degrees or more below the horizon, lasts 3.7 hours on December 15.
NASA POWER's 2001 to 2020 all-hours climatology puts mean cloud amount for the 1 degree cell around Rolleston at 66% across the year, from 63% in July to 71% in December. In the months with at least 4 hours of civil night Rolleston averages 66%, against a median of 66% for Glow towns in New Zealand.
Multiplying civil night by the clear share of the sky gives July the best score, 5.0 hours, ahead of June at 4.9. Rolleston's equinox months score 3.7 in March and 3.8 in September, the weeks SWPC links with larger storms.
Kp history
No whole Kp value puts the average oval edge over Rolleston by SWPC's rule, so the GFZ record has no threshold to count. SWPC's G4 row gives the typical latitude where aurora has been seen.
Share of UTC days in each calendar month whose highest 3-hour Kp reached the level. Kp history by year
Moon, next 30 nights
Over the 30 nights from Oct 2, the new moon falls on Oct 11 and the full moon on Oct 26, in Pacific/Auckland dates. 16 of the 30 nights at Rolleston have at least 2 moon-free dark hours inside 10 PM to 2 AM, and Oct 2 has the most at 4 h. Tonight Rolleston has 10 h 19 min of civil night, 6 h 24 min of it with the moon down.
- 2
63% lit
6.4 h
- 3
51% lit
7.3 h
- 4
40% lit
8.0 h
- 5
29% lit
8.5 h
- 6
20% lit
9.0 h
- 7
12% lit
9.3 h
- 8
5% lit
9.6 h
- 9
2% lit
9.9 h
- 10
0% lit
9.9 h
- 11
1% lit
9.7 h
- 12
4% lit
8.5 h
- 13
8% lit
7.3 h
- 14
14% lit
6.2 h
- 15
22% lit
5.2 h
- 16
30% lit
4.3 h
- 17
39% lit
3.5 h
- 18
48% lit
2.9 h
- 19
58% lit
2.4 h
- 20
67% lit
1.9 h
- 21
76% lit
1.6 h
- 22
84% lit
1.2 h
- 23
91% lit
0.8 h
- 24
96% lit
0.5 h
- 25
99% lit
0.1 h
- 26
100% lit
0.0 h
- 27
98% lit
1.1 h
- 28
93% lit
2.4 h
- 29
85% lit
3.6 h
- 30
76% lit
4.6 h
- 31
66% lit
5.4 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.
Within New Zealand
Among the 5 Glow towns in Canterbury, Rolleston ranks 3rd by dipole latitude against a regional median of 46.8 degrees; Timaru sits highest at 47.8. Among the 11 Glow towns in New Zealand, Rolleston ranks 9th by dipole latitude against a national median of 48.4 degrees; Invercargill sits highest at 50.2. On December 15 Rolleston gets 7.3 hours of civil night, 1st longest of 11 in New Zealand, where the median is 7.1.
Questions
- Can you see the southern lights in Rolleston?
- Rolleston sits at 46.8 degrees geomagnetic. The lowest NOAA storm level whose typical viewing latitude reaches it is G4 (Kp = 8, including a 9-). Even Kp 9 does not put the average oval edge overhead by SWPC's rule. Clear, dark sky over Rolleston still decides it.
- When is it dark enough in Rolleston?
- Every night at Rolleston has civil darkness. Tonight has 10 h 19 min, and December 15 has 7.3 hours.
- What is the best month for aurora in Rolleston?
- July, by civil night at Rolleston times the clear share of the sky from NASA POWER's 2001 to 2020 average.
- How cloudy is Rolleston in the dark months?
- About 66% mean cloud amount over Rolleston in the months with at least 4 hours of civil night, from NASA POWER's 2001 to 2020 all-hours climatology.
Nearby and related
Nearest Glow towns
Rolleston by month
Region and comparisons