Phoenix, Arizona – A G4 (Severe) geomagnetic storm, in effect for Jan. 20, is expected to reach Earth, prompting increased monitoring of technology and infrastructure across the Southwest, even as the region avoids the extreme Arctic cold affecting other parts of the country.
According to the NOAA Space Weather Prediction Center, a coronal mass ejection, or CME, launched from the Sun late last week is forecast to arrive late Sunday into Monday. Severe geomagnetic storms can disrupt satellite operations, GPS accuracy, radio communications, and long-distance power transmission systems, though impacts vary by latitude and local conditions.
The storm watch includes Arizona, New Mexico, Nevada, Utah, southern California, and west Texas. While the Southwest lies south of the regions most vulnerable to geomagnetic disturbances, officials note that the region’s reliance on long transmission corridors, satellite-based navigation, aviation traffic, and defense-related systems makes monitoring necessary during high-level solar activity.
NOAA officials emphasize that widespread power outages are not expected in the Southwest. However, utilities and operators of critical systems typically increase monitoring during G4-level storms to protect sensitive equipment and ensure grid stability.
For most residents, the solar storm will not produce noticeable effects on daily life. Cell phone service and internet connectivity are expected to remain largely unaffected. Some users may experience minor GPS inaccuracies, particularly in precision-dependent applications such as aviation, surveying, and timing systems.
Aurora displays are unlikely across much of the Southwest but could become faintly visible in far northern areas if storm conditions intensify beyond current forecasts.
Geomagnetic activity may gradually ease into Tuesday as space weather conditions stabilize.
