A strong geomagnetic storm is on the way: Who could see auroras

Multiple coronal mass ejections (CMEs) from the sun this week are expected to produce dazzling auroras across parts of Europe and North America Thursday night into Friday morning.

Northern light watchers are on alert Thursday night into Friday morning as a potentially dazzling display is forecast to light up the skies. Multiple explosions on the sun this week unleashed four bursts of plasma from the sun’s corona toward Earth. These bursts of plasma are known as coronal mass ejections or CMEs.

A rapid Earth-bound CME left the sun on Nov. 29 during a powerful M9.8-class solar flare eruption. But this isn't the only CME that left the sun this week. Wednesday's fast-moving outburst will merge with several slower upstream CMEs that left the sun a day earlier, on Nov. 28, creating a "Cannibal CME" that will likely trigger a strong geomagnetic storm.

Auroras will be visible in northern Europe, Canada, and Alaska. How far south the northern lights will be visible is uncertain. However, it’s possible the lights could light up the sky across parts of the northern Plains, Midwest, and Northeast. There’s even a chance they will be faintly visible into the Mid-Atlantic, southern Plains, and parts of California.

Powerful solar storms can disrupt technology. The incoming solar storm is expected to be large enough to produce auroras, but not large enough to cause any major technological disruptions. A watch for a G3 solar storm goes into effect at 7 p.m. ET Thursday evening. The scale for solar storms ranges from G1 to G5, with a G3 storm being categorized as strong.

With potentially dazzling lights in the forecast, you will want to get the cameras ready and check the WeatherRadar for the cloud cover forecast.