G1 – Minor Geomagnetic Storm Alert issued on October 13

A G1 – Minor Geomagnetic Storm Alert was issued on October 13, 2025. The alert indicates that the geomagnetic K-index reached a value of 5 at 05:21 UTC, with the synoptic period covering 03:00 to 06:00 UTC. According to the NOAA Space Weather Prediction Center, an active warning is in effect.

Potential impacts from this G1 – Minor event are expected primarily poleward of 60 degrees geomagnetic latitude. Weak power grid fluctuations are possible due to induced currents, and minor impacts on satellite operations may occur. Aurora could be visible at high latitudes, including the northern tier of the United States such as northern Michigan and Maine.

The current geomagnetic storm activity is primarily attributed to ongoing effects from a negative polarity coronal hole high-speed stream (CH/HSS). Solar wind parameters have been enhanced, with speeds peaking around 750 km/s, contributing to active to G1 – Minor geomagnetic storm conditions over the past 24 hours. The geomagnetic field is anticipated to reach active to G1 – Minor storm levels throughout October 13 as the CH/HSS influence persists.