ALERT: Geomagnetic K-index of 4 Alert issued on October 30

A Geomagnetic K-index of 4 Alert was issued on October 30, 2026. The alert was announced at 22:40 UTC, with the threshold being reached at 22:35 UTC. This alert remains active for the synoptic period from 21:00 to 24:00 UTC on October 30.

According to the alert, the primary area of impact is expected poleward of 65 degrees geomagnetic latitude. Potential impacts include weak power grid fluctuations due to induced currents. In addition, aurora may be visible at high latitudes, particularly in regions such as Canada and Alaska. These impacts are consistent with geomagnetic activity at this level.

The triggering event for this increased geomagnetic activity is associated with disturbances in the solar wind, as indicated by recent forecasts. Solar wind parameters showed the effects of a magnetic structure moving through the near-Earth environment on October 30, with the anticipated arrival of a recurrent, equatorial positive polarity coronal hole high speed stream (CH HSS) expected to continue influencing geomagnetic conditions into November 1. No Earth-directed coronal mass ejections were observed.