Northern lights tonight
Will you see the aurora tonight? NOAA's live forecast for your city: the aurora oval right now, the Kp index for the next three nights, the Kp your latitude needs and when it gets dark.
Now, Sunday, October 18, 10:58 PM UTC
Quiet geomagnetic conditions
NOAA aurora data updated at 10:18 PM UTC.
Choose your city to see whether the aurora could reach it tonight.
- Chance here
- Choose your city
- Kp now
- 1.67 (quiet)
- Kp needed here
- Choose your city
- Dark tonight
- Choose your city
- Moon
- Solar wind
- 415 km/s, Bz 2 nT
- Magnetic latitude
Your location stays in this browser.
WATCH: Geomagnetic Storm Category G1 PredictedNOAA SWPC, Oct 18, 5:24 PM UTC
Kp index: the last day and NOAA's forecast for the next three
The chart needs JavaScript; the forecast is in the table below.
Drag along the chart, or use the arrow keys, to see the globe and the verdict for any hour of the next three days. Each bar is a three-hour block (solid: observed, lighter: forecast); shaded columns are the dark hours at your place; the lines show the Kp your magnetic latitude needs, overhead and low on the horizon.
Kp forecast by three-hour block
| Day (UTC) | 00 | 03 | 06 | 09 | 12 | 15 | 18 | 21 |
|---|---|---|---|---|---|---|---|---|
| Sun, Oct 18 | 2 | 2.33 | 2 | 1.67 | 0.33 | 1.33 | 1.67 | 1.67 |
| Mon, Oct 19 | 2.33 | 2 | 1.33 | 2.67 | 3 | 3.67 | 4.67 | 4.33 |
| Tue, Oct 20 | 4.33 | 4.67 | 3.67 | 3 | 3 | 3 | 3.33 | 3.67 |
| Wed, Oct 21 | 3.33 |
Kp 5 and above is a geomagnetic storm (G1 to G5). Data: NOAA Space Weather Prediction Center (OVATION aurora model, planetary K index, alerts), refreshed every few minutes. Magnetic latitude: NOAA's WMM2025 dipole pole. Calculations of darkness and the Moon: Astronomy Engine. Map: Natural Earth.
How tonight’s answer is worked out
The verdict at the top combines three things for the place you choose. The first is NOAA’s OVATION model, which turns the solar wind measured upstream of Earth into a map of where visible aurora is likely over the next 30 to 90 minutes; the percentage is that model’s chance for your exact spot. The second is your magnetic latitude, which decides how strong a storm has to be before the aurora reaches you. The third is darkness: the aurora is not visible in daylight, so the tool works out when the Sun is at least 12 degrees below your horizon and whether a bright Moon is up.
When the oval itself is not over you, the tool checks how far away it is. NOAA says a bright aurora can be seen from as much as 1,000 kilometers away when conditions are right, low on the horizon facing the pole.
The Kp index and how far south the aurora reaches
The planetary K index, or Kp, measures geomagnetic activity on a scale from 0 to 9, in three-hour blocks. NOAA calls Kp 5 a G1 minor storm and Kp 9 a G5 extreme storm. According to NOAA, the equatorward edge of the aurora oval sits near 66 degrees magnetic latitude at Kp 0 and moves about 2 degrees closer to the equator with each step, reaching 48 degrees at Kp 9. At the highest levels the aurora may be seen overhead from the northern states of the USA.
Magnetic latitude is measured from the geomagnetic pole, which NOAA puts near 80.9 degrees north and 72.8 degrees west for 2025, so it differs from ordinary latitude: places in North America sit at a higher magnetic latitude than places in Europe at the same geographic latitude. The chart shows two lines for your place: the Kp needed for the aurora overhead, and the lower Kp that may bring it into view on the horizon.
When and where to look
NOAA’s advice is to go out at night and get away from city lights; the best aurora is usually within an hour or two of midnight, between about 10 PM and 2 AM local time. Look toward the pole, from a high spot with an open view of the horizon. A full Moon does not change the aurora itself but makes it look fainter. Clouds block it completely, so check your local cloud forecast as well.
Where the data comes from
Everything on this page comes from NOAA’s Space Weather Prediction Center and refreshes every few minutes: the OVATION aurora forecast, the planetary K index, the three-day Kp forecast issued by NOAA’s forecasters, the NOAA scales and the latest geomagnetic watches, warnings and alerts. The solar wind figures come from spacecraft at the L1 point between the Sun and Earth. A southward magnetic field (a negative Bz) lets solar wind energy into Earth’s magnetic field more easily, which is why it is shown next to the wind speed.
Common questions
Can I see the northern lights tonight?
For the next 24 hours NOAA expects the K index to reach 4.67. Choose your city above to see what that means where you are. It depends on three things at once: a strong enough geomagnetic storm for your magnetic latitude, a dark sky, and no clouds. The verdict at the top of this page checks the first two for your city every few minutes.
What is the Kp index right now?
Right now NOAA estimates the planetary K index at 1.67, quiet conditions for the three hours from 9:00 PM UTC. The K index runs from 0 (quiet) to 9 (extreme storm). Values of 5 and above are geomagnetic storms, G1 to G5 on NOAA’s scale.
What Kp do I need to see the aurora?
Following NOAA’s rule of thumb, take 66, subtract your magnetic latitude and divide by two: that is roughly the Kp at which the aurora’s edge is overhead. The aurora can show up low on the horizon a few Kp steps earlier when it is bright. The tool does this calculation for you once you choose your city.
What time is best to see the northern lights?
NOAA says the best displays usually come within an hour or two of midnight, between about 10 PM and 2 AM local time, but during a strong storm the aurora can appear as soon as it gets dark.
Does the Moon affect the northern lights?
A bright Moon makes the aurora look fainter without changing its actual brightness, so faint displays are easier to miss around full Moon. The tool tells you how much of the Moon is lit and whether it is above your horizon.
Can the aurora be seen from the Southern Hemisphere?
Yes. The southern lights, or aurora australis, form a matching oval around the south geomagnetic pole. Choose a city south of the equator and the map turns to the southern oval.
