G1 – Minor Geomagnetic Storm Watch issued for October 28 and 29, 2025

A G1 – Minor Geomagnetic Storm Watch was issued by NOAA SWPC, effective for October 28 and 29, 2025. The watch indicates the likelihood of minor geomagnetic storm conditions, with the highest predicted storm level being G1 (Minor) on both dates. No storm conditions are forecast for October 27. This watch supersedes all previous watches in effect.

Potential impacts from this geomagnetic storm are expected primarily for areas poleward of 60 degrees geomagnetic latitude. There may be weak power grid fluctuations, along with minor impacts to satellite operations. Auroras could become visible at high latitudes, including the northern tier of the U.S. such as northern Michigan and Maine.

The current forecast attributes the enhanced geomagnetic activity to the expected arrival of a coronal mass ejection (CME) that left the Sun on October 23. Further increases in geomagnetic activity on October 28 are likely to result from the influence of a large, positive polarity coronal hole. No significant solar flares were observed to trigger the watch.