The spectacular aurora borealis, the nighttime light display triggered by solar flares that has been so unusually prevalent since Friday, could be visible again on Sunday night in much of the United States as a powerful geomagnetic storm continues.
The aurora borealis, or northern lights, has been observed from locations much farther south than usual, including much of the United States, Britain and some parts of Central America.
The glowing green, pink and purple lights will be visible again on Sunday night in places with clear, dark skies, according to the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center.
“There’s a chance that what’s coming at us later today could be quite comparable to what we saw Friday into Friday night,” Mike Bettwy, the operations chief of the Space Weather Prediction Center, said on Sunday. “Our forecast is for it to be right up to that level.”
There were reports of the lights being visible in Puerto Rico, South Florida and parts of Central America on Friday night, Mr. Bettwy said, and it could happen again on Sunday night if the storm is as intense.
He said the aurora “ebbs and flows without much reason,” making it hard to predict the best time to view the phenomenon.
“Generally, the darker the sky is, the higher the chances that you’ll see it,” Mr. Bettwy said.
In places with a lot of bright lights, like a city, it is more difficult to see.
Cloudy weather can also block the view. This could pose a challenge for those hoping to see the northern lights in the central United States, where rain and storms are forecast.
Tony Fracasso, a meteorologist at the National Weather Service’s Weather Prediction Center, said that the best chances for clear skies would be in much of the West, as well as from Ohio toward the Mid-Atlantic and possibly in North Dakota and Minnesota.
New England was “a question mark,” he said.
In the United Kingdom, thunderstorms were moving north across Wales into northern England and Scotland on Sunday night, but it was clearer in the south and east.
If you are in a clear area, take a picture or record a video with your cellphone. The camera’s sensor is more sensitive to the wavelengths made by the aurora and may reveal an image different from what you can see with the naked eye.
This weekend’s show is the result of the most powerful geomagnetic storm to reach Earth since October 2003. When geomagnetic activity increases, auroras become brighter and more active, and they expand to regions where they are not usually seen.
The Space Weather Prediction Center has a five-level scale to rate geomagnetic storms. A watch was in place on Sunday for conditions to reach the fourth level or higher.
On Saturday, the storm’s conditions were at the third and the fourth levels, with a period of level-five conditions early in the day, the center said.
Geomagnetic storms can interfere with power grids, communications and navigations systems, but there had been no significant impacts from the storm as of Sunday morning, according to the Federal Emergency Management Agency.
The storm will continue into Monday, the Space Weather Prediction Center said.
