G2 – Moderate Geomagnetic Storm Watch issued for October 16, 2025

A G2 – Moderate Geomagnetic Storm Watch was issued for October 16, 2025, by the NOAA Space Weather Prediction Center. According to the official alert, the highest storm level is expected to reach G2 – Moderate on October 16, followed by G1 – Minor storm levels on October 17. No storm activity above G1 is predicted for October 15. This Watch supersedes any prior watches in effect.

Potential impacts are primarily expected in regions poleward of 55 degrees Geomagnetic Latitude. There is a potential for power grid fluctuations and voltage alarms in high-latitude power systems due to induced currents. Spacecraft may experience satellite orientation irregularities and increased drag on low Earth-orbit satellites. HF (high frequency) radio propagation may fade at higher latitudes. Additionally, aurora sightings may be possible as far south as New York to Wisconsin to Washington state.

The triggering event for this Watch is linked to several coronal mass ejections (CMEs) that originated from Active Region 4246 during M-class flare activity on the Sun, including an M1.2 flare occurring at 13:18 UTC on October 13, 2025. These CMEs are expected to begin impacting the near-Earth environment by late October 15, leading to the predicted geomagnetic storm conditions on October 16.