Geomagnetic K-index of 4 – Alert issued on April 2, 2026

A Geomagnetic K-index of 4 Alert was issued by the NOAA Space Weather Prediction Center at 02:20 UTC on April 2, 2026. The alert is valid for the synoptic period from 00:00 to 03:00 UTC, highlighting increased geomagnetic activity.

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

According to the latest forecast discussion, solar activity was at low levels, with only C-class flares observed. No significant Earth-directed coronal mass ejections were indicated. However, solar wind disturbances related to a negative polarity coronal hole high speed stream (CH HSS) are anticipated to become geoeffective around midday on April 2. The geomagnetic field is forecast to remain unsettled to potentially reach G1 – Minor Geomagnetic Storm levels in the following periods.