Early Sunday morning, G4 geomagnetic storm conditions had been reached. Such strong conditions have been known to bring the northern lights as far south as Alabama and northern California.

Early Sunday morning, G4 geomagnetic storm conditions had been reached. Such strong conditions have been known to bring the northern lights as far south as Alabama and northern California.

Early Sunday morning, G4 geomagnetic storm conditions had been reached. Such strong conditions have been known to bring the northern lights as far south as Alabama and northern California.

Early Sunday morning, G4 geomagnetic storm conditions had been reached. Such strong conditions have been known to bring the northern lights as far south as Alabama and northern California.

Federal officials say a G3 (strong) or G4 (severe) geomagnetic storm is possible, weather that could disrupt power systems, impede satellite operations and hamper radio communications.

A geomagnetic storm expected today and tomorrow has been upgraded to G4 (severe) by the National Oceanic and Atmospheric Administration (NOAA). Solar storms can disrupt GPS and GNSS signals before ...

We saw another G4 geomagnetic storm a few months after the G5 storm, which caused the northern lights to only be visible to cameras in Metro Atlanta.

The forecast predicted summerlike heat and the potential for northern lights due to a G4 geomagnetic storm, as indicated by the Space Weather Prediction Center. However, the storm, which required ...