A significant coronal mass ejection (CME) impacted Earth's magnetosphere on June 1, 2025, resulting in a severe (G4-class) geomagnetic storm. The CME, consisting of a large expulsion of plasma and magnetic field from the Sun’s corona, was triggered by a powerful M8.2-class solar flare from sunspot AR4100 on May 31, 2025.
The storm, monitored closely by agencies like the European Space Agency, caused immediate geomagnetic disturbances. These disturbances have the potential to disrupt high-latitude electrical grids and high-frequency radio communications. Satellite navigation systems, such as GPS, may also experience timing errors.
Geomagnetic storms arise from the interaction between the solar wind and Earth’s magnetosphere. The severity of the storm depends on the strength and orientation of the CME's magnetic field. Under favorable conditions, auroras could be visible at lower latitudes than usual. While not expected to surpass the intensity of the May 2024 storm, this event remains one of the most significant of the current solar cycle. Forecasters predict that storm levels will likely subside by June 3, 2025, potentially decreasing to G1-G2 (Minor-Moderate) levels.