Geomagnetic storms 25 July 2025

The kIndex is a measure of geomagnetic activity, ranging from 0 (quiet) to 9 (severe storm). A kIndex of 4 indicates a level of "unsettled" geomagnetic activity, which may still be relatively quiet compared to higher levels but can have some noticeable effects. At this level, fluctuations in the Earth's magnetic field can occur, often due to solar wind interactions and coronal mass ejections. For weather-sensitive individuals, a kIndex of 4 may lead to mild disruptions, primarily affecting those with heightened sensitivity to atmospheric changes, such as individuals with migraines, anxiety, or certain chronic conditions. Symptoms can include headaches, fatigue, and mood fluctuations, as these individuals may react to both the magnetic changes and the enhanced ionospheric currents associated with this level of geomagnetic activity. While the kIndex of 4 generally does not cause widespread disruptions, those sensitive to environmental changes may experience mild discomfort and should remain aware of their personal health responses during this period.