Illinois, United States
Northern lights in Oak Park
Answer
Tonight
Waiting on darkness
It is not civil-dark yet. The next dusk is listed below.
Observed 11:55 UTC, forecast 13:26 UTC, 91 min lead
Clock times in America/Chicago
Valid 12:00 to 13:00 UTC
Storm level needed
Oak Park sits at 41.88N 87.78W in Illinois, United States. The IGRF-14 centered dipole puts Oak Park at 50.7 degrees geomagnetic latitude, 8.8 degrees closer to the magnetic pole than its map latitude suggests. Oak Park sits at 50.7 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 8.
"aurora has been seen as low as Illinois and Oregon (typically 50° geomagnetic lat.)"
The nearest other Glow towns are Chicago (12 km), Evanston (19 km), Wheaton (27 km). Chicago sits 0.0 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 Oak Park has some civil darkness; the shortest month sample still has 7.5 hours. Every evening of the year at Oak Park clears Glow's dark-season bar of 4 hours of civil night between 18:00 and 06:00. Oak Park's longest night of the year, Dec 19, has 13 h 44 min of civil night.
Solar midnight at Oak Park, when the sun is lowest, falls at 23:46 on local clocks on December 15 and 00:51 on June 15. That is 14 min before midnight in December and 51 min after midnight in June, the gap set by daylight saving and the equation of time. So at Oak Park 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 | 13.4 h | 11.1 h | 71% | 3.9 h | |
| Feb | 12.3 h | 10.2 h | 70% | 3.7 h | |
| Mar | 11.1 h | 8.9 h | 66% | 3.8 h | |
| Apr | 9.6 h | 7.2 h | 63% | 3.6 h | |
| May | 8.3 h | 5.4 h | 64% | 3.0 h | |
| Jun | 7.5 h | 4.2 h | 56% | 3.3 h | |
| Jul | 7.9 h | 4.8 h | 48% | 4.1 h | |
| Aug | 9.1 h | 6.5 h | 48% | 4.7 h | |
| Sep | 10.5 h | 8.3 h | 46% | 5.7 hbest | |
| Oct | 11.9 h | 9.8 h | 58% | 5.0 h | |
| Nov | 13.1 h | 10.9 h | 63% | 4.8 h | |
| Dec | 13.7 h | 11.4 h | 73% | 3.7 h |
By the 15th-of-the-month sample, December is the darkest month at Oak Park with 13.7 hours of civil night and June the lightest at 7.5. Across the year Oak Park gets 3,899 hours of civil night. Astronomical night at Oak Park, the sun 18 degrees or more below the horizon, lasts 11.4 hours on December 15.
NASA POWER's 2001 to 2020 all-hours climatology puts mean cloud amount for the 1 degree cell around Oak Park at 60% across the year, from 46% in September to 73% in December. In the months with at least 4 hours of civil night Oak Park averages 61%, against a median of 61% for Glow towns in United States.
Multiplying civil night by the clear share of the sky gives September the best score, 5.7 hours, ahead of October at 5.0. Oak Park's equinox months score 3.8 in March and 5.7 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 8 or more, the level that puts the average oval edge over Oak Park, on 0% of days. At Oak Park's level the share runs from 0% in February to 1% in November, 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 8. 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 25, in America/Chicago dates. 15 of the 30 nights at Oak Park have at least 2 moon-free dark hours inside 10 PM to 2 AM, and Oct 5 has the most at 4 h. Tonight Oak Park has 11 h 16 min of civil night, 2 h 29 min of it with the moon down.
- 1
65% lit
2.5 h
- 2
54% lit
3.6 h
- 3
43% lit
4.8 h
- 4
32% lit
6.1 h
- 5
22% lit
7.4 h
- 6
13% lit
8.7 h
- 7
7% lit
9.9 h
- 8
2% lit
11.1 h
- 9
0% lit
11.6 h
- 10
0% lit
11.7 h
- 11
3% lit
11.7 h
- 12
7% lit
11.7 h
- 13
13% lit
11.1 h
- 14
20% lit
10.5 h
- 15
28% lit
9.7 h
- 16
36% lit
8.8 h
- 17
46% lit
7.8 h
- 18
55% lit
6.8 h
- 19
65% lit
5.7 h
- 20
74% lit
4.7 h
- 21
82% lit
3.5 h
- 22
89% lit
2.5 h
- 23
95% lit
1.3 h
- 24
99% lit
0.1 h
- 25
100% lit
0.0 h
- 26
98% lit
0.0 h
- 27
94% lit
0.2 h
- 28
87% lit
1.1 h
- 29
79% lit
2.1 h
- 30
68% lit
3.3 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.
Within United States
Among the 12 Glow towns in Illinois, Oak Park ranks 6th by dipole latitude against a regional median of 50.7 degrees; Waukegan sits highest at 51.2. Among the 137 Glow towns in United States, Oak Park ranks 104th by dipole latitude against a national median of 51.5 degrees; Fairbanks sits highest at 65.7. On December 15 Oak Park gets 13.7 hours of civil night, 92nd longest of 137 in United States, where the median is 13.8.
Questions
- Can you see the northern lights in Oak Park?
- Oak Park sits at 50.7 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 8. Clear, dark sky over Oak Park still decides it.
- When is it dark enough in Oak Park?
- Every night at Oak Park has civil darkness. Tonight has 11 h 16 min, and December 15 has 13.7 hours.
- What is the best month for aurora in Oak Park?
- September, by civil night at Oak Park times the clear share of the sky from NASA POWER's 2001 to 2020 average.
- How cloudy is Oak Park in the dark months?
- About 61% mean cloud amount over Oak Park 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 Oak Park?
- A 3-hour Kp of 8 or more, the level that puts the average oval edge overhead, occurred on 0% of days from 1996 to 2025 in the GFZ Potsdam record.
- Why does this page point to Chicago?
- Oak Park sits within 15 km of Chicago with the same rounded dipole latitude, Kp and dark season, so Glow treats Chicago as the main page for both.
Nearby and related
Nearest Glow towns
Oak Park by month
Region and comparisons