SWPC's NOAA geomagnetic, solar radiation and radio blackout scales summarize expected impacts and recommended awareness levels.
| Class | GOES 0.1-0.8 nm flux (W/m^2) | Notes |
|---|
| A | 10^-8 to <10^-7 | Lowest X-ray levels; background or tiny flares. |
| B | 10^-7 to <10^-6 | Small flares; generally minor impacts. |
| C | 10^-6 to <10^-5 | Moderate flares; can cause minor HF absorption. |
| M | 10^-5 to <10^-4 | Strong flares; can cause significant HF disruptions. |
| X | >=10^-4 | Extreme flares; can drive major radio blackouts. |
| Level | Descriptor | Typical Impacts |
|---|
| G1 | Minor | Localized power grid fluctuations and aurora near the poles. |
| G2 | Moderate | Voltage depressions, satellite charging, aurora over the northern U.S. |
| G3 | Strong | Transformer stress, HF radio degradation, widespread aurora. |
| G4 | Severe | Possible grid disturbances, satellite drag, global aurora visibility. |
| G5 | Extreme | High risk of grid outages, satellite failures, astronaut exposure. |
| Level | Descriptor | Typical Impacts |
|---|
| S1 | Minor | Slight radiation increase for polar aviation; satellites mostly unaffected. |
| S2 | Moderate | Single-event satellite upsets, elevated exposure for high-altitude flights. |
| S3 | Strong | Frequent satellite anomalies, astronauts and polar flights need mitigation. |
| S4 | Severe | Spacecraft anomalies common, serious exposure risk for crews. |
| S5 | Extreme | Critical satellite performance, severe radiation hazard for humans. |
| Level | Descriptor | Typical Impacts |
|---|
| R1 | Minor | Slight HF degradation on sunlit side. |
| R2 | Moderate | Short HF outages and GPS interference. |
| R3 | Strong | Intense HF blackouts and navigation degradation. |
| R4 | Severe | Complete HF loss and wide-area radio failure. |
| R5 | Extreme | Extended HF blackout with critical comm and nav impacts. |
Official NOAA dashboard with aurora forecasts, geomagnetic storms, and solar event summaries.
Orbital elements for weather satellites from Celestrak's NORAD elements feed.
Celestrak satellite metrics are unavailable right now.
Unable to retrieve the SpaceWx table right now.
To avoid large downloads, the full feed is only fetched when the selected start date is before 2020-01-01.
GFZ Niemegk publishes the latest planetary Kp/AP numbers plus a probabilistic Kp outlook.
GFZ nowcast data is unavailable at the moment.
Three-hourly Kp/ap values published by GFZ Niemegk (latest rows include nowcast values).
Monthly Kp index tables with 8 daily intervals, daily sum, Ap/Cp and quality codes.
Daily Kp/ap values with supporting solar indices from 1932 onward. Full interval columns are available in the unified summary below.
ISGI (International Service of Geomagnetic Indices) provides IAGA-endorsed indices such as Kp, aa, am, Dst, PC and AE.
The Royal Observatory of Belgium's SILSO service tracks the Estimated International Sunspot Number (EISN).