Harrisburg, Pennsylvania – A rare G4 (Severe) solar storm is expected to impact Earth on Jan. 20, prompting increased monitoring of Pennsylvania’s power grid and other critical technology systems as federal space weather officials track incoming solar activity.
According to the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center, a coronal mass ejection (CME) launched from the Sun late last week is forecast to arrive late Sunday into Monday. G4-level geomagnetic storms are uncommon and can interfere with power transmission systems, satellite operations, GPS accuracy, and some radio communications, particularly across large and complex electrical networks.
Pennsylvania’s extensive transmission infrastructure, industrial energy demand, and role as a regional power corridor increase the importance of grid stability during severe space weather events. While the state sits south of the most geomagnetically exposed regions, NOAA officials emphasize that widespread power outages are not expected, though utilities may take precautionary measures to protect sensitive equipment.
For most residents, the solar storm itself will not be noticeable. Experts explain that geomagnetic activity can introduce electrical currents into long transmission lines, reducing the grid’s margin for error. Grid operators may increase system monitoring, adjust loads, or implement protective actions if conditions intensify.
Cell phone service and internet connectivity are expected to remain largely unaffected. However, minor GPS inaccuracies are possible, particularly affecting aviation operations, rail systems, and precision timing used by emergency services and utilities.
As a visible side effect, auroras may be visible across northern Pennsylvania, especially in rural or higher-elevation areas, if geomagnetic activity strengthens beyond current forecasts.
NOAA forecasters say geomagnetic activity could continue at lower levels into Tuesday.
