Red sun phenomenon freaks out people as storm Ophelia draws air from Sahara closer to north UK.
Hurricane-force winds from Storm Ophelia battered Ireland and the UK on Monday.
And a strange phenomenon came with it. Parts of the country have been plunged into darkness at various times throughout the day, with some people reporting a yellow or orange glow in the sky.
The skies were so dark and gloomy above parts of the country that street lights automatically came on and cars were forced to use their headlights.
It began in the west of the UK on Monday morning and has spread eastwards through the day.
Dr David Reynolds, senior meteorologist from The Weather Channel, says up to four conditions have come together to create the conditions.
- Winds were strong over Iberia on Sunday, so dust from there has being raised and blown to the UK. Ophelia was to the west of Portugal on Sunday, although it doesn’t necessarily need a hurricane to cause this and a regular, north Atlantic low would also work if other necessary conditions are met. There have also been serious fires in Portugal. Dr Reynolds said: “Some of the dust may be particulates from the fires, although I think regular fine-grained dust would account for the majority.”
- The cold front of Ophelia moved across southern Britain on Monday morning and was very weak – this meant there was not much rain to wash the dust out.
- The winds are still southerly, despite the cold front coming through. Usually winds would veer and fresher, clearer Atlantic air would come in behind a cold front – but this won’t happen until later today. Dr Reynolds said: “As fresher air moves in later today, expect the colouration to gradually fade.”
- On top of this, much of the cloud at the moment is at mid-levels. The lower levels and upper levels are fairly clear, which allows more sunlight to penetrate the cloud deck and, combined with the fairly high cloud base, allows conditions to be bright at surface.
- Dr Rob Thompson, from the University of Reading’s meteorology department, said the strange sky was caused by dust in the atmosphere , but that it could have originated from the Sahara. He said as Ophelia passed Africa on its journey north, it sucked up the dust, which is now in our atmosphere.
“It’s not that unusual, it happens quite regularly,” he said. “Because of the way that Ophelia has tracked it’s pulling a lot of dust up from the south.
“I think the absolute giveaway is that tomorrow we’ll find our cars covered in orangey yellow dust.”
He said their radar has picked up the dust in the atmosphere: “We can definitely see that there is something in the atmosphere – from about one kilometre up there’s a layer of something. The storm is sucking the wind up from the right area.”There’s always dust in the atmosphere but we find the Saharan dust is bigger than the normal stuff.”