G1 – Minor Geomagnetic Storm Alert issued on October 30

A G1 – Minor Geomagnetic Storm Alert was issued on October 30, 2025, after the Geomagnetic K-index reached 5 at 16:45 UTC. The alert is valid for the synoptic period from 15:00 to 18:00 UTC. NOAA’s Space Weather Prediction Center has indicated that an active warning is in effect and the situation is being monitored closely.

According to NOAA’s official classification, a G1 – Minor Geomagnetic Storm can primarily affect areas poleward of 60 degrees geomagnetic latitude. Potential impacts include weak power grid fluctuations due to induced currents, minor impacts on satellite operations, and possible auroral activity visible at high latitudes, including the northern tier of the United States such as northern Michigan and Maine.

This geomagnetic storm activity was triggered by persistent high speed solar wind streams associated with a positive polarity coronal hole. Solar wind speeds ranged from approximately 430–585 km/s, and the continued influence of coronal hole high speed streams is expected through November 1. No Earth-directed coronal mass ejections were observed during this period.