NOAA Predicts Geomagnetic Storm and Possible Northern Lights in 20 U.S. States

Forbes reported that the National Oceanic and Atmospheric Administration (NOAA) is forecasting a G1 or G2-class geomagnetic storm for Saturday, April 4, through Sunday, April 5. This storm could make the Northern Lights visible in northern U.S. states and Canada, with up to 20 states potentially affected.

The forecast stems from a coronal mass ejection that impacted Earth's magnetic field on April 3, combined with ongoing influences from a high-speed solar wind stream.

The geomagnetic storm is expected to reach G1 levels on April 4, with possible periods of G2 intensity due to waning coronal mass ejection effects and negative polarity coronal hole high-speed streams. According to NOAA, active conditions may continue on April 5. A 90%-lit waning gibbous moon rising after midnight could reduce visibility of faint auroras.

The Northern Lights are most likely to appear low on the northern horizon in states near the Canada border, such as Alaska and northerly parts of Washington, Idaho, Montana, North Dakota, South Dakota, Minnesota, Wisconsin, Michigan, and Maine. If a G2-class storm occurs, faint auroras might be visible in northern regions of Oregon, Wyoming, Nebraska, Iowa, Illinois, Indiana, Ohio, New York, Vermont, and New Hampshire.

States farther north generally have better odds for clear sightings, enhanced by low light pollution and clear skies.

com, along with apps such as Aurora Now, My Aurora Forecast, or Glendale Aurora. These tools provide data on the interplanetary magnetic field's Bz component, which indicates solar energy entry into Earth's magnetosphere; a southward Bz of -5 nT or stronger often signals aurora activity.

The exact timing depends on solar wind speed, making real-time monitoring essential.