G1 – Minor Geomagnetic Storm Alert issued on October 13

A G1 – Minor Geomagnetic Storm Alert was issued on October 13, 2025 at 02:57 UTC. The alert follows a threshold K-index of 5 reached at 02:56 UTC for the synoptic period between 0000 and 0300 UTC.

Potential impacts primarily affect areas poleward of 60 degrees geomagnetic latitude. Weak power grid fluctuations may occur, and minor impacts on spacecraft operations are possible. Auroras may be visible at high latitudes, including parts of the northern United States such as northern Michigan and Maine. This event is categorized as G1 – Minor on the NOAA Space Weather Scale.

The geomagnetic activity is being driven by enhanced solar wind conditions related to the persistent influence of a negative polarity coronal hole high speed stream (CH/HSS). Solar wind speeds increased to around 750 km/s, with magnetic field fluctuations contributing to the geomagnetic storm. The NOAA SWPC forecast expects geomagnetic field activity to remain at active to G1 (Minor) storm levels on October 13, 2025 due to ongoing effects from the CH/HSS.