A huge outburst on the sun is about to score a "direct hit" on Earth, and could cause minor disruptions to power grids in northern latitudes.
People in north UK may be able to see northern lights or aurora as particles from the sun hit the Earth’s magnetic field.
The Space Weather Prediction Center, part of the US National Oceanic and Atmospheric Administration, issued a geomagnetic storm warning on Sunday for Monday and Tuesday.
The warning suggested the storm could affect power grids in some areas, and satellites, but in practice these effects are likely to be minor.
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Aurora could be visible in some parts of the UK, the Met Office said.
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The Met Office said: "On the 11 October a coronal mass ejection is expected to arrive at Earth, with minor to moderate geomagnetic storms likely, resulting in enhanced auroral activity during 11 October.
"There is a slight chance of aurora reaching the far north of England and Northern Ireland tonight, but cloud breaks and therefore sightings are more likely in Northern Ireland.
"Minor storms may continue into 12 October, before a fast wind from a coronal hole may arrive, perhaps continuing the rather active period of geomagnetic activity."
Coronal mass ejections are large clouds of solar plasma and magnetic fields released into space after a solar eruption.
Stretching over millions of miles, they can cause northern lights when they hit Earth’s atmosphere.
Solar storms are ranked from G1 to G5, with stronger storms having the potential to cause radio blackouts.
This week’s storm will be at the lower end of the scale, the Met Office said.
It added that aurora could continue into the week, saying: “Aurora is possible through 11th and 12th across much of Scotland, although cloud amounts are increasing, meaning sightings are unlikely for most.
Nasa describes a geomagnetic storm as an interaction in Earth’s magnetosphere, saying: “When a coronal mass ejection or high-speed stream arrives at Earth it buffets the magnetosphere.
“If the arriving solar magnetic field is directed southward it interacts strongly with the oppositely oriented magnetic field of the Earth.
“The Earth's magnetic field is then peeled open like an onion allowing energetic solar wind particles to stream down the field lines to hit the atmosphere over the poles.”
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