A powerful geomagnetic storm lit up skies across much of the US late Tuesday and early Wednesday, giving people in dozens of states a rare chance to see the northern lights, and forecasters say that more auroral activity could be visible on Wednesday night too.
The aurora borealis, commonly known as the northern lights, was reported in more than a dozen states, stretching from New York to Washington state to Texas, Oklahoma and Tennessee. Photos of the glowing colorful skies also poured in on social media from Nevada, Massachusetts, Georgia, Alabama, Montana, Alaska, Wyoming, California, Louisiana, New Mexico, Florida, South Carolina, North Carolina, Nebraska, Iowa, Idaho, South Dakota and more.
Aurora borealis occurs when charged solar particles from the sun collide and interact with gases in the Earth’s upper atmosphere.
The National Oceanic and Atmospheric Administration’s (Noaa) Space Weather Prediction Center (SWPC) issued a severe G4 geomagnetic storm watch for 11 and 12 November, the second highest rating on its scale, after fast-moving coronal mass ejections (CME) were hurled out by the sun.
In a video post on late on Tuesday night, Shawn Dahl, a forecaster at the SWPC in Boulder, Colorado, said that “a lot of geomagnetic storm activity” was occurring, and said that two or three anticipated CMEs had already reached Earth and “packed quite a punch” and “already reached G4 severe level conditions”.
Dahl said that the two CMEs were “profoundly stronger than we anticipated”.
He said that forecasters do not believe that the third CME has arrived yet, and said that they are anticipating its arrival around midday ET on Wednesday.
In a video update on Wednesday morning, Dahl said that the two CMEs that already reached Earth had a magnetic strength “eight times stronger than what’s normal” and said that the conditions are “favorable at the moment for continued activity”.
In a release on Wednesday, Noaa forecasters said that they expect the third CME, which is still expected to arrive around noon ET, to be the “final and most energetic” of the three.
Meteorologist Marc Chenard, of the Weather Prediction Center, told the New York Times that the northern lights could return again on Wednesday night around the country, though clouds may block views for those in parts of the west coast and north-east.
As of 9am ET on Wednesday, the SWPC said that G3 conditions are currently being observed and that “G4 conditions with a chance for higher levels remain possible throughout the day as another CME is expected to arrive midday (EST)”.
