Northern Lights in Duluth
Minnesota (Great Lakes)
Aurora needs a dark sky, enough geomagnetic activity and clear weather. This page covers all three for Duluth, Minnesota, month by month.
Best Time to Go
Best months for an overhead display: March, September, October.
- Overhead display
- Kp 5 or higher
- Faint glow, northern horizon
- Kp 4 or higher
Tonight, Live
Live Aurora Maps
Aurora Oval Right Now
Tonight's Viewline
Dark enough all year.
Best time of night: the aurora here is usually strongest around 12am standard time (1am while clocks are on daylight saving time), from about 10pm to 2am standard time.
The activity counts here cover geomagnetic activity and darkness only, not clouds. Clear, dark skies are needed to see aurora.
How to Read This Page
Three things have to line up to see the northern lights: darkness, enough geomagnetic activity for the latitude, and a clear sky.
Dark hours are the hours each night with the sun more than 12 degrees below the horizon, read on the 15th of the month.
Activity is the Kp index, a 0 to 9 scale of geomagnetic activity measured every 3 hours. Each place needs a certain Kp for a faint glow to the north and a higher Kp for a display overhead. The counts show how often dark nights reached that level from 1991 to 2025.
The best months are the three months when the largest share of dark nights reached the level. They often fall around the equinoxes, in March and in September and October, rather than in midwinter: geomagnetic storms are more common then, because the tilt of the Earth's magnetic field around the equinoxes makes it easier for the Sun's magnetic field, carried by the solar wind, to connect with it.
The activity counts do not include clouds, and history is not a forecast. Check the live maps on the night, before you head out.
Hours of Darkness Each Month
Mostly Clear Nights and Cold by Month
| Month | Mostly clear nights in a typical month | Average low | Average snow depth |
|---|---|---|---|
| January | about 18 nights | 3°F-16°C | 9 in23 cm |
| February | about 18 nights | 4°F-16°C | 10 in24 cm |
| March | about 17 nights | 18°F-8°C | 7 in18 cm |
| April | about 14 nights | 30°F-1°C | 4 in9 cm |
| May | about 15 nights | 40°F5°C | under 1 in1 cm |
| June | about 15 nights | 50°F10°C | nonenone |
| July | about 20 nights | 58°F14°C | nonenone |
| August | about 20 nights | 58°F14°C | nonenone |
| September | about 19 nights | 50°F10°C | nonenone |
| October | about 17 nights | 38°F3°C | 1 in3 cm |
| November | about 15 nights | 25°F-4°C | 5 in12 cm |
| December | about 15 nights | 11°F-12°C | 8 in19 cm |
A mostly clear night here has at least 2 dark hours with under 50 percent cloud cover (a satellite estimate for the area), counted from 2001 to 2025.
Mostly clear nights and active nights are counted separately, so they are not always the same nights.
Cloud, low and snow figures are satellite and model estimates for the area around each place, 2001 to 2025, not readings from a local weather station. They are averages, not a forecast.
Biggest Nights on Record Here
- November 11, 2025: Kp 9
- May 10, 2024: Kp 9
- August 23, 2005: Kp 9
- November 9, 2004: Kp 9
- October 28, 2003: Kp 9
The strongest dark nights here from 1991 to 2025, each strong enough for a display overhead at Duluth. Clear, dark skies needed.
Moon Guide
Moonlight washes out a faint aurora. The darkest skies come in the week around each new moon:
The Solar Cycle
In October 2024 NASA and NOAA announced that the Sun had reached the maximum period of Solar Cycle 25, which they said could last about a year. Source: NASA
Month by Month in Duluth
| Month | Dark hours | Nights reaching Kp 5 (overhead) | Nights reaching Kp 4 (low on the horizon) |
|---|---|---|---|
| January | 12.6 | about 2 nights | about 6 nights |
| February | 11.4 | about 2 nights | about 6 nights |
| March | 9.9 | about 3 nights | about 7 nights |
| April | 8.0 | about 2 nights | about 7 nights |
| May | 6.2 | about 2 nights | about 5 nights |
| June | 5.0 | about 1 night | about 3 nights |
| July | 5.6 | about 1 night | about 3 nights |
| August | 7.4 | about 2 nights | about 5 nights |
| September | 9.3 | about 3 nights | about 7 nights |
| October | 10.9 | about 3 nights | about 7 nights |
| November | 12.3 | about 3 nights | about 7 nights |
| December | 13.0 | about 1 night | about 6 nights |
Nights in a typical month. Clear, dark skies needed.
When Is the Best Time to See the Northern Lights in Duluth?
Best months for an overhead display: March, September, October. Dark enough all year.
Also in Great Lakes
Dark hours: time with the sun more than 12 degrees below the horizon on the night of the 15th. Kp needed: from the place's corrected geomagnetic latitude (AACGM-v2) and NOAA's average position of the auroral oval; the horizon figure adds our own allowance of about 3 degrees. Nights: definitive Kp, 1991 to 2025, counting only nights with darkness.
Kp index data: Geomagnetic Observatory Niemegk, GFZ Helmholtz Centre for Geosciences, CC BY 4.0. Matzka, J., Stolle, C., Yamazaki, Y., Bronkalla, O. and Morschhauser, A., 2021. The geomagnetic Kp index and derived indices of geomagnetic activity. Space Weather, https://doi.org/10.1029/2020SW002641 CC BY 4.0
The month figures are history, not a forecast.
Cloud, temperature and snow data: NASA Langley Research Center (LaRC) POWER Project, funded through the NASA Earth Science/Applied Science Program. NASA POWER