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Science|Northern Lights Shine for a Second Night
https://www.nytimes.com/2025/11/12/science/how-to-see-the-northern-lights-wednesday.html
A geomagnetic storm made the aurora borealis visible across a swath of the United States again on Wednesday, illuminating the skies as far south as Arizona.
Published Nov. 12, 2025Updated Nov. 13, 2025, 7:44 a.m. ET
A surprisingly powerful northern lights display dazzled much of the Northern Hemisphere Wednesday, illuminating the sky as far south as Arizona in the United States. It was the second straight night of the phenomenon in much of the country.
On Tuesday night, the lights became visible following a coronal mass ejection — a burst of charged particles from the sun. These particles carry their own magnetic fields, and when they collide with Earth’s magnetic field, they set off a geomagnetic storm, forming the aurora.
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There were two explosions of material from the sun that reached Earth on Tuesday, and material from a third entered the atmosphere later Wednesday.
The Space Weather Prediction Center has a scale for these storms, which runs from G1, a “minor” storm, to G5, or an “extreme” storm. The strength of the storm helps dictate how strong the aurora is and how far south it can be seen. That’s why the lights can be somewhat common in northern places like Iceland and Alaska, but a stronger storm can send people as far south as Alabama scrambling to the window.
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On Tuesday, the geomagnetic storm reached G4 levels for six hours, and on Wednesday night, it reached G3 levels.
Charles Carr, a senior space weather forecaster at the Space Weather Prediction Center, said conditions were expected to wane, with a slim chance of viewing the lights on Thursday night.
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“Things are starting to mellow out now,” he said. Areas of Canada were most likely to see the lights, “if there was some activity,” he said.
In Britain, the aurora was visible again as far south as London, though cloud cover obscured the view in many places.
Nazaneen Ghaffar is a Times reporter on the Weather team.
Amy Graff is a Times reporter covering weather, wildfires and earthquakes.
