Aurora Forecast Tonight: Where To Look

Live planetary Kp: 0.67 (Quiet)

On a clear, dark night the aurora may come into view low on the northern horizon from about 66°N — the Arctic Circle — northern Alaska, northern Canada and Tromsø.

NOAA expects Kp near 3.7 over the next 24 hours, peaking around Kp 5.0 (G1 Minor).

NOAA SWPC, 2026-09-23 12:00 UTC. Refreshes every five minutes.

The place list above is the viewline: roughly where the aurora may become visible low on the northern horizon tonight, on a clear and properly dark night, at the Kp being measured right now. It is not where the aurora is overhead. Standing under the curtains means being inside the auroral oval itself, several degrees of latitude further north. From the viewline you are looking at the top of something hundreds of kilometres away, which usually reads as a pale grey-green glow rather than the saturated colour in photographs — a camera on a few seconds of exposure picks up colour your eyes cannot.

Kp is necessary but nowhere near sufficient. Four other things have to line up: real darkness, which high-latitude summers never deliver; a clear sky to the north; a moon that is down or new; and enough distance from town that its glow does not sit exactly where you are looking. A Kp 7 night under overcast is nothing at all, and a Kp 5 night from a dark rural site with a clean northern horizon can be memorable. Local cloud, moon phase and darkness windows are on the stargazer page.

Timing matters as much as the number. The oval is brightest near magnetic midnight, so the hours either side of local midnight are worth more than the whole evening before them, and activity comes in substorm bursts that flare for twenty to forty minutes and then subside. Give it time rather than checking once. The weeks around the equinoxes are statistically the most productive of the year, because the geometry between the Earth's field and the incoming solar wind couples more easily then.

Treat the multi-day outlook as a planning tool and nothing firmer. The honest lead time is short: the solar wind measured at L1 gives fifteen to sixty minutes of warning, and it is the southward magnetic field there, not the speed, that decides whether a display happens. The Kp index on this page is the confirmation that it already did, which is why aurora chasing rewards watching the upstream data and going outside anyway.

Aurora forecast FAQ

Will I see the aurora tonight?
Compare the live Kp at the top of this page with the viewline it puts you on, then check the rest: full darkness, clear sky, a low or absent moon, no city glow to your north, and an unobstructed northern horizon. Kp decides whether the aurora is within reach of your latitude at all; the rest of that list decides whether you actually see it.
What Kp do I need at my latitude?
From northern Alaska, northern Canada or Tromsø, quiet conditions are often enough, and Fairbanks or Reykjavík need only Kp 2. Kp 5 brings the viewline to the US–Canada border near 50°N, Kp 6 to the northern edge of Washington, Montana and North Dakota, and Kp 7 as far south as Minnesota, Wisconsin and Maine. Oregon, Iowa and Pennsylvania take a G4, and seeing it from the latitude of Kansas or Virginia takes a G5, which happens a few times a solar cycle.
What time of night and which direction?
Look north, and concentrate on the hours around local midnight, when your longitude rotates under the most active part of the auroral oval. Displays arrive in substorm bursts that brighten for twenty to forty minutes and then fade, so a blank sky at 10pm says little about midnight. Autumn and spring weeks are statistically the most productive.
How far ahead can an aurora forecast be trusted?
The NOAA three-day Kp outlook is a planning tool, not a promise — it tells you which nights are worth staying up for. Real confidence arrives fifteen to sixty minutes ahead, when the solar wind reaches the spacecraft at L1 and you can see whether the magnetic field is pointing south. NOAA’s OVATION model turns that into a thirty-minute nowcast of where the oval will sit.

The rest of the space weather desk

The full space weather monitor carries every feed on one screen: scales and alerts, flare timelines, Kp history, solar wind plasma, sunspot regions, coronagraph frames and SDO imagery.

  • Solar flares — Current GOES X-ray class, and what today's solar activity actually affects.
  • Kp index — The live planetary Kp, its G-scale storm level, and what it means for aurora.
  • Solar wind — Live speed, density and Bz from the DSCOVR spacecraft, roughly an hour upstream.