Springfield, Illinois – A rare G4 (Severe) solar storm is expected to impact Earth on Jan. 20, prompting increased monitoring of Illinois’ power grid and 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, interconnected electrical networks.
Illinois plays a key role as a Midwest power and transportation hub, with long-distance transmission lines supporting major population centers, manufacturing corridors, rail networks, and aviation traffic centered around the Chicago region. NOAA officials emphasize that widespread power outages are not expected, but utilities typically increase monitoring during severe space weather events to protect transformers and maintain grid stability.
For most residents, the solar storm itself will not be noticeable. Experts explain that geomagnetic activity can introduce electrical currents into long transmission lines, slightly reducing the grid’s margin for error. Grid operators may increase system monitoring, adjust loads, or take precautionary measures 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, freight rail systems, shipping on Lake Michigan, and precision timing systems used by utilities and emergency services.
As a secondary effect, auroras may be visible across northern Illinois, especially in rural areas or near Lake Michigan, if geomagnetic activity strengthens beyond current forecasts.
NOAA forecasters say geomagnetic activity could persist at lower levels into Tuesday.
