The northern lights could make an appearance starting Monday, as a powerful solar storm surges toward Earth, potentially producing a dazzling display across the northern tier of the United States and the Midwest into Tuesday.
Scientists at the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center issued a geomagnetic storm watch for Monday through Tuesday, after a medium-to-strong solar flare erupted from the sun on Saturday.
That flare launched what is known as a full-halo coronal mass ejection — a large expulsion of plasma and magnetic field from the sun — aimed directly toward Earth.
The Weather Prediction Center expects the storm to arrive late on Monday, producing a G2-level, or moderate, geomagnetic storm at first.
By Tuesday, as the bulk of the storm passes, conditions could intensify to G3 (strong) storm conditions, capable of driving the aurora much farther south than usual, including parts of Iowa, Oregon and Pennsylvania.
The weather, however, may complicate the view.
Bryan Jackson, a meteorologist at the Weather Prediction Center, said on Sunday that an upper-level disturbance was expected to move into the Northern Plains, bringing clouds over the Dakotas Sunday night.
A low-pressure system along the Washington coast will likely bring cloud cover across much of Washington State and perhaps over the northern Rockies.
Farther east, however, skies should be more favorable.
“Clear areas would be New England, particularly northern New England, the Great Lakes area and parts of Montana,” Mr. Jackson said, though he noted that a weather system moving up the Eastern Seaboard could bring widespread cloud cover there.
By Monday night, the cloudy skies across the Northwest are forecast to shift farther east.
“The Great Lakes would still be pretty clear,” Mr. Jackson said. “Minnesota, parts of the Dakotas and Montana would be clearer than Sunday night.”
The northern lights, or aurora borealis, are streaks of colorful light that paint the nighttime sky and are most common in the skies over locations closer to the North Pole.
Different gases create different hues. Oxygen in the atmosphere produces green or red light during an aurora, while nitrogen gives rise to shades of blue and purple.
They occur when eruptions on the sun’s surface, known as coronal mass ejections, emit material that triggers geomagnetic storms when they interact with Earth’s magnetic field.
Nazaneen Ghaffar is a Times reporter on the Weather team.
The post Northern Lights Could Put on a Show for Large Sections of the U.S. appeared first on New York Times.