G1 – Minor Geomagnetic Storm Alert issued on April 30

A G1 – Minor Geomagnetic Storm Alert was issued on April 30, 2026, after the K-index reached 5, indicating minor geomagnetic storm conditions. The alert is active for the synoptic period from 21:00 to 24:00 UTC on April 30, 2026.

According to the NOAA Space Weather Prediction Center, the area of impact is primarily poleward of 60 degrees geomagnetic latitude. Potential impacts include weak power grid fluctuations and minor impacts to satellite operations. Aurora may be visible at high latitudes, such as the northern tier of the United States, including northern Michigan and Maine.

The alert was triggered by the onset of a negative polarity coronal hole high-speed stream (-CH HSS), which was anticipated for mid April 30. These enhanced solar wind conditions are expected to persist through May 1, returning to near nominal levels by May 2. No Earth-directed coronal mass ejections (CMEs) were observed in recent data.