Ontario, Canada
Northern lights in Nepean
Answer
Tonight
Waiting on darkness
It is not civil-dark yet. The next dusk is listed below.
Observed 11:49 UTC, forecast 13:20 UTC, 91 min lead
Clock times in America/Toronto
Storm level needed
Nepean sits at 45.34N 75.72W in Ontario, Canada. The IGRF-14 centered dipole puts Nepean at 54.5 degrees geomagnetic latitude, 9.2 degrees closer to the magnetic pole than its map latitude suggests. Nepean sits at 54.5 degrees geomagnetic. The lowest NOAA storm level whose typical viewing latitude reaches it is G3 (Kp = 7). By SWPC's rule the average oval edge is overhead only at Kp 6.
"aurora has been seen as low as Illinois and Oregon (typically 50° geomagnetic lat.)"
The nearest other Glow towns are Ottawa (9 km), Kanata (16 km), Orléans (22 km). Ottawa sits 0.1 degrees higher 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 Nepean has some civil darkness; the shortest month sample still has 7.0 hours. Every evening of the year at Nepean clears Glow's dark-season bar of 4 hours of civil night between 18:00 and 06:00. Nepean's longest night of the year, Dec 20, has 14 h 3 min of civil night.
Solar midnight at Nepean, when the sun is lowest, falls at 23:58 on local clocks on December 15 and 01:03 on June 15. That is 2 min before midnight in December and 1 h 3 min after midnight in June, the gap set by daylight saving and the equation of time. So at Nepean the darkest hour sits near the middle of SWPC's 10 PM to 2 AM window in winter.
Month by month
| Month | Night | Civil | Cloud | Clear dark | |
|---|---|---|---|---|---|
| Jan | 13.7 h | 11.3 h | 70% | 4.1 h | |
| Feb | 12.4 h | 10.2 h | 67% | 4.1 h | |
| Mar | 11.0 h | 8.7 h | 64% | 4.0 h | |
| Apr | 9.3 h | 6.7 h | 65% | 3.3 h | |
| May | 7.8 h | 4.5 h | 64% | 2.8 h | |
| Jun | 7.0 h | 2.9 h | 61% | 2.7 h | |
| Jul | 7.4 h | 3.8 h | 56% | 3.3 h | |
| Aug | 8.8 h | 6.0 h | 56% | 3.9 h | |
| Sep | 10.4 h | 8.0 h | 54% | 4.8 hbest | |
| Oct | 12.0 h | 9.7 h | 68% | 3.8 h | |
| Nov | 13.3 h | 11.0 h | 72% | 3.7 h | |
| Dec | 14.0 h | 11.6 h | 76% | 3.4 h |
By the 15th-of-the-month sample, December is the darkest month at Nepean with 14.0 hours of civil night and June the lightest at 7.0. Across the year Nepean gets 3,863 hours of civil night. Astronomical night at Nepean, the sun 18 degrees or more below the horizon, lasts 11.6 hours on December 15.
NASA POWER's 2001 to 2020 all-hours climatology puts mean cloud amount for the 1 degree cell around Nepean at 64% across the year, from 54% in September to 76% in December. In the months with at least 4 hours of civil night Nepean averages 64%, against a median of 67% for Glow towns in Canada.
Multiplying civil night by the clear share of the sky gives September the best score, 4.8 hours, ahead of January at 4.1. Nepean's equinox months score 4.0 in March and 4.8 in September, the weeks SWPC links with larger storms.
Kp history
From 1996 to 2025, the GFZ Potsdam record shows a 3-hour Kp of 6 or more, the level that puts the average oval edge over Nepean, on 3% of days. At Nepean's level the share runs from 1% in December to 5% in October, while storm days with Kp 5 or more made up 10%.
Share of UTC days in each calendar month whose highest 3-hour Kp reached Kp 6. Kp history by year
Moon, next 30 nights
Over the 30 nights from Oct 1, the new moon falls on Oct 10 and the full moon on Oct 26, in America/Toronto dates. 15 of the 30 nights at Nepean have at least 2 moon-free dark hours inside 10 PM to 2 AM, and Oct 5 has the most at 4 h. Tonight Nepean has 11 h 15 min of civil night, 2 h 10 min of it with the moon down.
- 1
66% lit
2.2 h
- 2
55% lit
3.3 h
- 3
43% lit
4.5 h
- 4
32% lit
5.9 h
- 5
22% lit
7.2 h
- 6
14% lit
8.5 h
- 7
7% lit
9.8 h
- 8
3% lit
11.1 h
- 9
0% lit
11.7 h
- 10
0% lit
11.7 h
- 11
3% lit
11.8 h
- 12
7% lit
11.8 h
- 13
12% lit
11.4 h
- 14
19% lit
10.8 h
- 15
27% lit
10.1 h
- 16
36% lit
9.2 h
- 17
45% lit
8.2 h
- 18
55% lit
7.1 h
- 19
64% lit
6.0 h
- 20
73% lit
4.8 h
- 21
82% lit
3.7 h
- 22
89% lit
2.5 h
- 23
95% lit
1.4 h
- 24
99% lit
0.1 h
- 25
100% lit
0.0 h
- 26
98% lit
0.0 h
- 27
94% lit
0.0 h
- 28
88% lit
0.8 h
- 29
79% lit
1.9 h
- 30
69% lit
3.1 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 Canada
Among the 38 Glow towns in Ontario, Nepean ranks 11th by dipole latitude against a regional median of 53.0 degrees; Kenora sits highest at 58.2. Among the 131 Glow towns in Canada, Nepean ranks 94th by dipole latitude against a national median of 55.3 degrees; Yellowknife sits highest at 68.5. On December 15 Nepean gets 14.0 hours of civil night, 94th longest of 131 in Canada, where the median is 14.2.
Questions
- Can you see the northern lights in Nepean?
- Nepean sits at 54.5 degrees geomagnetic. The lowest NOAA storm level whose typical viewing latitude reaches it is G3 (Kp = 7). By SWPC's rule the average oval edge is overhead only at Kp 6. Clear, dark sky over Nepean still decides it.
- When is it dark enough in Nepean?
- Every night at Nepean has civil darkness. Tonight has 11 h 15 min, and December 15 has 14.0 hours.
- What is the best month for aurora in Nepean?
- September, by civil night at Nepean times the clear share of the sky from NASA POWER's 2001 to 2020 average.
- How cloudy is Nepean in the dark months?
- About 64% mean cloud amount over Nepean in the months with at least 4 hours of civil night, from NASA POWER's 2001 to 2020 all-hours climatology.
- How often is activity high enough for Nepean?
- A 3-hour Kp of 6 or more, the level that puts the average oval edge overhead, occurred on 3% of days from 1996 to 2025 in the GFZ Potsdam record.
- Why does this page point to Ottawa?
- Nepean sits within 15 km of Ottawa with the same rounded dipole latitude, Kp and dark season, so Glow treats Ottawa as the main page for both.
Nearby and related
Nearest Glow towns
Nepean by month
Region and comparisons