G1 – Minor Geomagnetic Storm Alert issued on October 19

A G1 – Minor Geomagnetic Storm Alert was issued on October 19, 2025, following the detection of a geomagnetic K-index of 5. The alert was issued at 00:50 UTC and is valid during the synoptic period from 00:00 to 03:00 UTC. This alert indicates that minor geomagnetic storm conditions are affecting the Earth’s magnetic field.

According to the alert, the area of impact is expected to be primarily poleward of 60 degrees geomagnetic latitude. Potential impacts include weak power grid fluctuations due to induced currents, minor impacts on satellite operations, and possible visibility of auroras at high latitudes, such as in northern Michigan and Maine. The event is classified at the G1 – Minor level on the NOAA geomagnetic storm scale.

The storming conditions are occurring in response to glancing influences from coronal mass ejections (CMEs) that departed the Sun between October 13 and October 15. Enhanced solar wind parameters have contributed to the elevated geomagnetic activity, with forecasts indicating that G1 – Minor storming is expected to continue on October 19 as CME influences persist, followed by corotating interaction region effects. Additional active geomagnetic periods are likely through October 21 as negative polarity coronal hole high-speed streams (CH HSS) dominate.