Space Weather Live
REAL-TIME KP INDEX · SOLAR WIND · GEOMAGNETIC STORM ALERTS · DATA: NOAA SWPC
Auto-refreshes every 2 minutes
Aurora Alert pulls live data from NOAA's Space Weather Prediction Center every two minutes: the Kp index, the Bz component of the interplanetary magnetic field, solar wind speed and density, and NASA's CME tracking data. Put together, these numbers answer one question. Is the aurora likely to be visible tonight, and from how far south. The numbers below are what NOAA's satellites are reporting right now, not a forecast made hours ago.
Based on Bz, solar wind speed & density from current readings.
Ground-truth magnetometer data: SuperMAG ↗
Red arrow on image = noon meridian
Full NOAA OVATION forecast →
Aurora Visibility by Kp
| Kp 0–2 | Aurora only near magnetic poles: Alaska, Norway, Iceland |
| Kp 3–4 | Northern Canada, Scandinavia, southern Alaska |
| Kp 5 | G1 Storm: northern US border states, northern Europe |
| Kp 6 | G2 Storm: Oregon, Wisconsin, New York, Germany |
| Kp 7 | G3 Storm: California, Pennsylvania, UK |
| Kp 8–9 | G4-G5 Extreme: Aurora visible at mid-latitudes globally |
What Is Space Weather?
Space weather refers to conditions on the Sun and in the solar wind that can affect Earth's magnetic field, satellites, power grids, radio communications, and GPS. Geomagnetic storms, rated G1-G5, are caused by coronal mass ejections (CMEs) interacting with Earth's magnetosphere. The Kp index measures global geomagnetic activity every 3 hours on a scale of 0–9.
A geomagnetic storm starts on the Sun, days before it reaches Earth. When a coronal mass ejection erupts, it carries a cloud of charged particles and magnetic field outward at speeds that can exceed a million miles an hour. If that cloud is aimed at Earth, it typically arrives one to three days later. NOAA and NASA track these eruptions from the moment they leave the Sun, which is why storm forecasts can give days of warning, even though the exact strength of the impact isn't known until the cloud passes a satellite stationed near the L1 Lagrange point, about a million miles sunward of Earth, usually 15 to 60 minutes before it reaches us.
Understanding Solar Wind Bz
The Bz component of the interplanetary magnetic field is the single most important aurora predictor. When Bz turns negative (southward), it connects with Earth's northward magnetic field, allowing solar energy in to drive geomagnetic storms. A sustained Bz of −10 nT or lower significantly increases aurora chances. Data from NOAA SWPC.
Bz can flip between positive and negative repeatedly over a single night, which is why the same Kp number can produce a dramatic display on one night and nothing at all on another. The live IMF chart on this page updates by the minute, while Kp only updates every three hours, so watching Bz directly is often a better real-time read on what's actually happening overhead.
How This Dashboard Works
This dashboard pulls directly from NOAA's Space Weather Prediction Center and NASA's DONKI database, the same real-time feeds forecasters and researchers use, filtered down to the numbers that actually matter for spotting aurora. The Kp index and forecast come from NOAA's models. Solar wind speed, density, and the Bz field come from satellites stationed near the L1 Lagrange point, which see solar wind conditions before they reach Earth. CME data comes from NASA's DONKI database, tracking eruptions from the moment they leave the Sun. Everything on this page refreshes automatically every two minutes.
Reading the CME Tracker
The CME tracker above shows two views of the same event. The horizontal timeline plots when a coronal mass ejection erupted from the Sun against when it's predicted to reach Earth, connected by a dashed line. The looping view below it shows recent CMEs as expanding arcs moving outward from the Sun over a 10-day window, giving a sense of direction and speed at a glance. Not every CME is aimed at Earth. Direction matters as much as speed, and only eruptions with an Earth-directed trajectory pose a real threat for a geomagnetic storm.