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Space weather warnings explained

The Met Office issues a number of different notifications triggered by space weather activity.

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or forecast space weather conditions change to such an extent that the forecaster considers a watch or a warning is no longer valid.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 Proton 100Mev Integral Flux above 1pfu   Time extended
Alert & Summary Proton 100Mev Integral Flux above 1pfu   None
Warning, Alert & Summary Proton 100Mev Integral Flux >10pfu S1 Warning - time extended
Warning, Alert & Summary Proton 100Mev Integral Flux >100pfu S2 Warning - time extended
Warning, Alert & Summary Proton 100Mev Integral Flux >1,000pfu S3 Warning - time extended
Warning, Alert & Summary Proton 100Mev Integral Flux >10,000pfu S4 Warning - time extended
Warning, Alert & Summary Proton 100Mev 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
       

 

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