G1 – Minor Geomagnetic Storm Watch issued for October 12 and 13, 2025

A G1 – Minor Geomagnetic Storm Watch was issued for October 12 and 13, 2025. The NOAA Space Weather Prediction Center released this alert on October 10, 2025, at 19:27 UTC, indicating that minor geomagnetic storm conditions are likely to occur, with the highest storm level expected on those two dates. No geomagnetic storm activity is predicted for October 11, 2025.

Potential impacts from this event are primarily expected poleward of 60 degrees geomagnetic latitude. Weak power grid fluctuations may be observed, and minor impacts on satellite operations are possible. Aurora sightings may be visible at high latitudes, including the northern tier of the United States such as northern Michigan and Maine. These impacts are consistent with typical conditions during a G1 – Minor Geomagnetic Storm.

According to the latest NOAA SWPC forecast discussion, this watch was triggered by the expected influence of a recurrent, negative polarity coronal hole high speed stream (CH HSS). This feature is forecast to become geoeffective from late on October 11 through October 12, 2025, causing elevated solar wind speeds and magnetic field strength. No Earth-directed coronal mass ejections (CMEs) have been identified in recent coronagraph imagery.