G1 – Minor Geomagnetic Storm Alert issued on June 5

A G1 – Minor Geomagnetic Storm Alert was issued by NOAA Space Weather Prediction Center on June 5, 2026. The alert is valid for the synoptic period from 21:00 to 24:00 UTC, after the geomagnetic K-index reached 5 at 23:24 UTC during ongoing disturbed geomagnetic conditions.

According to the official alert, the area of impact is primarily poleward of 60 degrees Geomagnetic Latitude. Potential impacts include weak power grid fluctuations due to induced currents, minor impacts on satellite operations, and the possibility of auroras visible at high latitudes. Locations such as the northern tier of the United States, including northern Michigan and Maine, may experience auroral displays. These effects correspond to the G1 – Minor level on the NOAA Space Weather Scale.

The triggering conditions for this Alert are linked to enhanced solar wind parameters following the arrival of multiple coronal mass ejections (CMEs) from June 3. Solar wind speed sharply increased, and magnetic field fluctuations were observed beginning at 04:24 UTC, persisting throughout June 5. Forecasts indicate these elevated solar wind conditions will continue into early June 6, with geomagnetic activity expected to decline to active and eventually quiet levels thereafter.