SEATTLE — Chances to see the northern lights are tapering off into the weekend in Washington state as a geomagnetic storm that collided with Earth's atmosphere on Thursday lessens in intensity.
The Space Weather Prediction Center (SWPC) is calling for a G1 storm on Friday night, which is considered to be "minor." At this intensity, the aurora is "commonly visible at high latitudes," according to the SWPC. The view line for the aurora is in southern Washington, but people will likely need to be farther away from city light pollution to spot it.
Thursday night's aurora was visible all throughout Washington state as a powerful G4 storm arrived. The Geomagnetic storm scale is measured from G1 to G5, with G5 being the most powerful.
The type of geomagnetic storm that causes the aurora borealis is called a Coronal Mess Ejection (CME) - it's a type of solar storm that blasts solar material into space. When that material collides with the Earth's atmosphere, the particles glow different colors as they shed energy.
Solar material takes a while to travel through space. The CME that impacted Earth on Oct. 10 left the surface of the sun on Oct. 8.
Solar storms of this type can have detrimental impacts on technology and communication systems. An event like a CME can change the structure of Earth's outer atmosphere, where signals pass back and forth between satellites and technology on the ground. However, the ability to forecast these types of disruptions allows the public and commercial industries to account for potential impacts.