Appearances of the aurora borealis are expected to be likely on Monday night following an intense geomagnetic storm that struck the Earth on Sunday.
The coronal mass ejection (CME) emerged from the Sun on Friday evening and struck the planet’s magnetosphere on Sunday morning.
NOAA’s Space Weather Prediction Center reported that the event raised geomagnetic storm levels to at least G3 over the weekend, with changes occurring based on “variations in solar wind as the CME continues to pass over Earth.”
Beginning on Sunday and continuing into Monday, NOAA reported that G1 through G4 levels had been reached, conditions under which “the aurora may become visible over much of the northern half of the country,” with appearances that may be visible as far south as parts of Alabama and northern California.
“G3 (Strong) or higher storm levels remain possible into the evening as CME progression continues,” the agency said.
By Monday morning, although there were signs that the CME had weakened, solar wind speeds remained elevated and capable of inducing geomagnetic storms.
These storm conditions result from plasma that erupts from the Sun during a CME, which bombards the Earth and can potentially interfere with radio transmissions and telecommunications systems, such as those relied on by pilots for communication with air traffic controllers, who may be required to rely on satellite communication systems as a backup under severe geomagnetic storm conditions.
The most significant solar flare event space weather forecasters have observed in many years occurred in December, which did result in some interference to radio communications.
However, the G4-class geomagnetic storm that resulted from this weekend’s CME was the strongest storm that has been observed since 2017, according to Tony Phillips at SpaceWeather.com.
NOAA advises that the public should not be concerned about the potential effects of Sunday’s CME, although skywatchers may want to be on the lookout for the auroral displays that are likely to occur.
Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. He can be reached by email at micah@thedebrief.org. Follow his work at micahhanks.com and on X: @MicahHanks.