ALERT: Geomagnetic K-index of 4 Alert issued on August 28

A Geomagnetic K-index of 4 Alert was issued on August 28, 2026 by the NOAA Space Weather Prediction Center. The alert indicates that active geomagnetic conditions were observed beginning at 15:00 UTC and are expected to persist during the synoptic period from 15:00 UTC to 18:00 UTC.

Potential impacts from this activity are primarily expected poleward of 65 degrees geomagnetic latitude. Weak power grid fluctuations may occur due to induced currents. In addition, auroras may be visible at high latitude locations such as Canada and Alaska.

According to the latest Forecast Discussion from SWPC, enhanced solar wind conditions under the influence of a positive polarity coronal hole high speed stream (CH HSS) contributed to the elevated geomagnetic activity. Solar wind parameters showed increased magnetic field intensity and higher wind speeds during the alert period.