A powerful geomagnetic storm is creating a rare and spectacular opportunity to witness the aurora borealis, or Northern Lights, across a wide swath of the United States and parts of Europe. This is driven by multiple solar particles hurtling toward Earth at high speeds.
The National Oceanic and Atmospheric Administration (NOAA) has issued a G3-level geomagnetic storm watch. It indicates strong storm conditions expected to last from the night of April 15 into April 16, 2025. The level of storm is significant but not extreme, and it is capable of producing vivid auroral displays visible much farther south than usual. It includes states like Oregon, Illinois, Michigan and even Kentucky.
The aurora borealis occurs when charged particles from the sun collide with gases in Earth’s upper atmosphere, exciting oxygen and nitrogen atoms and causing them to glow in vibrant colors such as green, purple, red and sometimes blue.
These colored lights are confined to high-latitude regions near the poles, but during strong geomagnetic storms, the auroras can be seen at mid-latitudes, offering a rare spectacle for many residents across the northern and central U.S.
NOAA’s Space Weather Prediction Centre reported that the storm activity began with the arrival of a shockwave associated with the CMES on the morning of April 15. The storm is expected to weaken by the night of April 16 but may continue to cause heightened geomagnetic activity for several days.
The Kp index, which measures geomagnetic activity on a scale from 0 to 9, is forecasted to reach levels consistent with a G3 storm, signalling strong disturbances in Earth’s magnetic field.
Regions with the highest probability of seeing the Northern Lights include Alaska, Washington, Oregon, Montana, North Dakota, Minnesota, Michigan and parts of the Northeast, such as Vermont and Maine.
Under optimal conditions, auroras might also be visible in northern Idaho, Wyoming, Nebraska, Iowa, Illinois, New York and Pennsylvania. Clear, dark skies away from city lights will provide the best viewing experience, with peak visibility typically between 10 pm and 2 am local time.
While the aurora is a breathtaking natural phenomenon, geomagnetic storms can also disrupt technology. The charged particles can interfere with satellite operations, GPS and radio communications and power grids. Satellite components may experience surface charging and low Earth orbit satellites might require orientation adjustments.
There is also a radiation risk for astronauts and high-altitude flights. However, NOAA notes that these effects are usually manageable and that the public should remain aware but not alarmed.
This geomagnetic storm is part of the sun’s current solar maximum phase, the peak of its approximately 11-year activity cycle. During this time, sunspots, solar flares and CMES become more frequent and intense, increasing the likelihood of such space weather events. Scientists expect more geomagnetic storms and auroral displays throughout 2025 as solar activity remains elevated.
For those eager to witness the Northern Lights, experts recommend checking aurora forecasts from NOAA or dedicated apps. Also, find dark locations with clear skies and use cameras with long exposure settings to capture the often faint lights.