Connecticut residents who missed seeing the northern lights on Tuesday could get a second chance to see them this week.
On Wednesday, the National Oceanic and Atmospheric Administration's (NOAA) Space Weather Prediction Center released a "very rare" watch for a G4-level or higher geomagnetic storm. The storm could cause the northern lights to be visible on Thursday or Friday, with the best chance to see them being Thursday, according to NOAA.
The geomagnetic storm that caused the northern lights to be visible earlier this week reached a G3 level. In May, the strong geomagnetic storm that allowed several parts of the United States, including Connecticut, to see colorful skies reached a G5 level, although it was originally predicted to be a G4-level storm.
"This is the second time in 20 years (for NOAA) to release a watch for this magnitude," Bryan Brasher, a project manager for NOAA's Space Weather Prediction Center, said.
The northern lights, or Aurora Borealis, are a result of strong geomagnetic activity. The event occurs when geomagnetic activity causes particles in the Earth's atmosphere to collide and take charge near the Earth's poles, which causes the lights, according to NOAA. The geomagnetic activity stems from a coronal mass ejection, or CME, which is an eruption of solar material.
The CME that is expected to create "highly elevated geomagnetic activity" is predicted to arrive Thursday morning to midday Eastern time, according to NOAA experts.
NOAA said its predictions about the intensity of the CME are based on estimated potential only, and the organization will not know its "true intensity potential" until it arrives one million miles from Earth.
Shawn Dahl, service coordinator for NOAA's Space Weather Prediction Center, said that the CME is moving faster than the CME that caused the northern lights to be visible in May, but Thursday's geomagnetic storm is not expected to be as extreme as the May event, which involved a release of a series of coronal mass ejections at once.
Dahl and other NOAA experts said that central eastern states, including Connecticut, and some lower Midwestern states may be able to see the northern lights days after the CME reaches Earth.
"Think of it as a strong cold front moving across the U.S.," Dahl said. "It may take a while for the extreme cold temperatures to show up after it arrives - with (geomagnetic storms) it's the same; effects may not show up for a bit after arrival."
If the geomagnetic storm watch changes to a warning and develops further into an alert, Connecticut residents should be able to see the G4-level event develop into northern lights within a few hours of darkness and in areas "outside of light-polluted skies," according to NOAA.
Those hoping to see the northern lights can track current space weather conditions on NOAA's aurora dashboard, which provides information on where the auroral lights will be in the next few minutes.
The Space Weather Prediction Center notes that the storm may cause voltage control problems, GPS system issues and the possibility of creating anomalies in satellite operations. The organization said that it contacted the North American Electric Reliability Corporation and Federal Emergency Management Agency ahead of the storm in case of technology and power issues, especially in light of Hurricane Milton.