SpaceWeatherTracker

Four things have to line up: enough geomagnetic activity (Kp) for your latitude, a dark sky with little moonlight, clear weather, and a clear view toward the pole. Strong activity cannot be seen through cloud or twilight. Check the live Kp index and aurora forecast here, then your local cloud forecast.

Space weather describes the changing conditions of the Sun, the solar wind and Earth's magnetic environment. Solar flares, coronal mass ejections and fast solar wind can disturb Earth's magnetic field, producing aurora and, in strong events, affecting radio, GPS, satellites and power grids.

Kp is NOAA's 0-to-9 index of global geomagnetic disturbance. Kp 4 and below is below storm level, while Kp 5 or higher counts as a geomagnetic storm (G1). As Kp rises, the auroral oval expands toward the equator, so aurora can be seen at progressively lower latitudes.

NOAA rates space weather on three scales from 1 to 5: G for geomagnetic storms (based on Kp), S for solar radiation storms, and R for radio blackouts caused by solar flares. Level 1 is minor and level 5 is extreme. Most days sit at or near zero on all three.

Live readings come from public NOAA Space Weather Prediction Center feeds, such as the Kp index, solar wind and GOES X-ray flux, and from NASA's DONKI database for coronal mass ejections. Where a feed provides an observation time, pages show that source time rather than when you loaded the page.