Space Weather Scales

Quick guide to geomagnetic storms (G), solar radiation storms (S), and radio blackouts (R) and what they typically do to power grids, satellites, aircraft and radio links.

G – Geomagnetic S – Solar Radiation R – Radio Blackouts

Geomagnetic storms G1 – G5

The highlighted card below shows the current status of Earth’s magnetic field driven by solar wind and CMEs.

Minor

Small fluctuations in the grid and mild effects on satellites at high latitudes.

Kp 5 or less Frequent

Moderate

Voltage alarms at high latitudes and more drag on low-orbit spacecraft.

Kp 6 Common

Strong

Grid operators may need corrections; satellite navigation and HF radio can become patchy.

Kp 7 Occasional

Severe

Widespread voltage control problems and some protective system misoperations possible.

Kp 8 Rare

Extreme

Possible grid collapse or blackout over wide areas; strong currents in pipelines and cables.

Kp 9 Very rare

Solar radiation storms S1 – S5

The highlighted card shows the current level of energetic particles that affect satellites and polar routes.

Minor

Slight increased radiation exposure for crew and passengers on high latitude flights.

Protons 10 MeV Frequent

Moderate

Possible single-event upsets in satellites; enhanced dose for high-latitude flights.

Protons 10 MeV Occasional

Strong

Can require re-routing of polar flights and cause noise in imaging sensors on spacecraft.

Protons 10 MeV Rare

Severe

Significant radiation hazard to astronauts; possible deep-charging problems for satellites.

Protons 10 MeV Very rare

Extreme

Extremely high radiation levels dangerous to astronauts and potentially damaging to satellites.

Protons 10 MeV Extremely rare

Radio blackouts R1 – R5

The highlighted card shows current X-ray flare conditions impacting HF radio and GNSS accuracy.

Minor

Weak or minor degradation of HF radio at high latitudes; occasional GNSS issues.

X-ray M1 Frequent

Moderate

Limited HF radio blackout in sunlit region and degradation of low-frequency navigation signals.

X-ray M5 Common

Strong

Wide-area blackout of HF radio on sunlit side of Earth; loss of radio contact for about an hour.

X-ray X1 Occasional

Severe

HF radio blackout on most of the sunlit side of Earth for hours; serious GNSS disruptions.

X-ray X10 Rare

Extreme

Complete HF radio blackout on the entire sunlit side of Earth; lasting for many hours.

X-ray X20+ Very rare