A geomagnetic storm warning has been issued by the The US Space Weather Prediction Centre after 17 flares burst from the same location on the surface of the Sun - creating a 'Cannibal Coronal Mass Ejection'. G3 is a 'strong' storm on the scale which ranges from 1 - minor - to 5 - extreme.
The storm could impact technology and could also mean the Aurora Borealis - the Northern Lights - being visible across much or all of the UK. Normally the lights would only commonly be visible in the north of Scotland, but could now stretch across much of the country.
John Keen of AuroraWatchUk said: "Things are going to get very interesting on the night of March 31. There were 17 flares from a sunspot group 4 at M class. We are looking at G2 magnetic storms possibly G3 if the CME impacts combine. This might bring UK-wide Auroras. "
A G3 warning means there could be temporary loss of high-frequency radio comms and low-frequency navigation signals - signals used in stav nav and in communication with ships and planes. A cannibal CME occurs when flares swallow up solar material ejected ahead of them - combining into very strong magnetic forces.
The SWPC said: "A G3 (Strong) geomagnetic storm watch is now in effect for March, 31 2022. A second, faster Coronal Mass Ejection (CME) erupted later on 28 March associated with an M1 flare at 3:23 pm EDT (1923 UTC).
"Analyses indicated the CME speed as approximately 841 km/s, and model guidance suggests this CME will overtake the day’s earlier CME and arrive during the early evening of 30 March into early morning of 31 March (EDT).
"Forecast confidence of an Earth-directed component is good, with moderate confidence of timing and intensity."
The alert adds: "Impacts to technology from a G3 storm generally remain small, but it can drive the aurora further equatorward of its polar home."
The Northern Lights could be seen much further south in the UK than normal, according to the Met Office.
The lights should be visible at around 3am, if the skies are clear - as far south as the Midlands and South East England.
