The KP index explained for drone pilots

What the KP index measures, why a geomagnetic storm can degrade drone GPS accuracy, which KP values to watch, and where to check the forecast.

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The KP index measures disturbances of the Earth's magnetic field on a scale from 0 (quiet) to 9 (extreme storm). It is published every three hours by GFZ Potsdam from a network of magnetic observatories.

Why drone pilots care

During a geomagnetic storm the upper atmosphere is disturbed, and the satellite signals your drone uses for positioning (GPS, GLONASS, Galileo, BeiDou) travel through it. Positioning can become less accurate, which shows up as drift in a hover or a less precise return to home. Strong storms may also affect compass readings.

Which values to watch

KPActivityWhat to do
0–3Quiet to unsettledNormal flying
4ActiveFly with extra attention to the satellite count
5 or moreGeomagnetic stormConsider postponing precision flights

Storms from KP 5 upward are the ones space-weather agencies classify as geomagnetic storms.

How to use it

  • Check the KP forecast together with the number of locked satellites: a high KP matters most when the satellite count is already low.
  • Keep the drone within sight and be ready to fly manually if the position becomes unstable.

Drone Weather Forecast shows the KP index for every forecast hour and colours it red above your limit (4 by default, adjustable), next to the satellite count for your position.

Check the wind for your drone before every flight

Drone Weather Forecast compares the hourly forecast, gusts, KP index and satellites with your drone model. Free on Android and iOS, no ads.