Space weather warnings explained
What do our space weather notifications mean and why have they been issued?
A full list of the notifications is available in the table below.
Watch is a long lead time message for potential increases in geomagnetic activity only
Warning is issued when certain conditions are expected for a period of time
Alert is issued when an event threshold has been crossed
Summary is issued at the end of an event, confirming the start and end time and peak measurement during the event.
Cancellation may be issued when either actual or forecast space weather conditions change to such an extent that the forecaster considers a watch or a warning is no longer valid.
| Type | Event | NOAA scale | Updated / Extended |
| Radio Blackout Alerts and Summaries | |||
| Alert & Summary | Radio Blackout – X-ray event > M5 | R2 | None |
| Alert & Summary | Radio Blackout – X-ray event > X1 | R3 | None |
| Alert & Summary | Radio Blackout – X-ray event > X10 | R4 | None |
| Alert & Summary | Radio Blackout – X-ray event > X20 | R5 | None |
| Geomagnetic Watches, Warnings and Alerts | |||
| Watch | Geomagnetic storm ≥G3 expected | Updated for severity or time | |
| Warning | Geomagnetic Sudden Impulse warning | None | |
| Alert | Geomagnetic Sudden Impulse | None | |
| Warning | Geomagnetic K-index of 7 expected | G3 | Time extended |
| Warning | Geomagnetic K-index of 8 expected | G4 | Time extended |
| Warning | Geomagnetic K-index of 9 expected | G5 | Time extended |
| Alert | Geomagnetic K-index of 5 | G1 | None |
| Alert | Geomagnetic K-index of 6 | G2 | None |
| Alert | Geomagnetic K-index of 7 | G3 | None |
| Alert | Geomagnetic K-index of 8 | G4 | None |
| Alert | Geomagnetic K-index of 9 | G5 | None |
| Proton Flux Warnings, Alerts and Summaries | |||
| Warning, Alert & Summary | Proton 100MeV Integral Flux above 1pfu | Warning - time extended | |
| Warning, Alert & Summary | Proton 10MeV Integral Flux >10pfu | S1 | Warning - time extended |
| Warning, Alert & Summary | Proton 10MeV Integral Flux >100pfu | S2 | Warning - time extended |
| Warning, Alert & Summary | Proton 10MeV Integral Flux >1,000pfu | S3 | Warning - time extended |
| Warning, Alert & Summary | Proton 10MeV Integral Flux >10,000pfu | S4 | Warning - time extended |
| Warning, Alert & Summary | Proton 10MeV Integral Flux >100,000pfu | S5 | Warning - time extended |
| Electron Flux Warnings, Alerts and Summaries | |||
| Warning | Electron 2MeV Integral Flux >1,000pfu | Extended | |
| Alert & Summary | Electron 2MeV Integral Flux >1,000pfu | None | |
