An “unusual” reddish sky and red-looking sun have been reported across parts of England.
The phenomenon has been seen in the South West, West Midlands, North West and North East.
BBC weather presenter Simon King said it was due to the remnants of Hurricane Ophelia dragging in tropical air and dust from the Sahara.
He added that debris from forest fires in Portugal and Spain was also playing a part.
The dust has caused light to be refracted and reflected in longer wavelengths, making it appear red.
He said: “Ophelia originated in the Azores where it was a hurricane and as it tracked its way northwards it dragged in tropical air from the Sahara.”
This meant dust from the Sahara was brought with it, he said.
“The dust gets picked up into the air and goes high up into the atmosphere, and that dust has been dragged high up in the atmosphere above the UK,” Mr King explained.
“Because the dust is so high, light from the sun is scattered in the longer wavelengths, which is more the red part of the spectrum, so it appears red to our eyes.”
The Met Office said the “vast majority” of the dust was as a result of forest fires in Iberia, which have sent debris into the air and that has been dragged north by Ophelia.