Aurora hunters around the world are eagerly awaiting the explosion of super-hot plasma known as a coronal mass ejection (CME) that will hit Earth tonight. A CME that quickly bound to Earth was separated from the Sun by a powerful M9.8 solar flare on November 29.

But that’s not the only thing. The fast plasma burst will combine with several slower CMEs above the one leaving the sun the previous day (November 28) to form a “Cannibal CME” that is likely to trigger a strong geomagnetic storm similar to the November 5 event. Auroras and STEVE increased worldwide.

If Cannibal CME strikes as predicted, the US National Oceanic and Atmospheric Administration (NOAA) is predicting strong (G3) geomagnetic storms with a spectacular aurora forecast for the US.

NOAA rates geomagnetic storms on a scale of G1 to G5, which can cause increases in aurorae around the poles and minor power fluctuations. This extreme level could cause a complete shutdown of HF (high frequency) radio waves on the entire sunny side of the Earth for several hours.

What should we expect?

The last G3 storm on November 5 produced spectacular auroras around the world, with northern lights reaching as far away as southern Greece and Turkey. Astrophotographer Gareth Mon Jones captured a stunning image of the aurora borealis above Penmon Lighthouse on Anglesey on November 5.

“Great display on Anglesey tonight. My girlfriend was delighted to see one of the best northern lights seen in a long time,” Jones wrote on X.

Stephen Lomas managed to photograph the mysterious STEVE above Dunstanburgh Castle in Northumberland, England.

“This was the most powerful aurora image I have seen in my 8 years of photography,” Lomas told Space.com. “The important thing was to see the crown and also to see STEVE!”

Meteorologist Angel Henriques was working the evening shift at the National Weather Service in Glasgow, northeastern Montana, when a colleague alerted him to the aurora light show.

“He was collecting photos of himself while a colleague wrote, ‘GO INTO THE GARDEN,'” Henriques told Space.com. “I took my tripod to the darkest part of the office next to the radar and took some unforgettable photos.”

If the next geomagnetic storm is similar to the one we experienced on November 5, we could be in for a real surprise.