The insects, which look similar to rainfall on radars, were detected by the Met Office on Friday, as people reported sightings on social media.

The day was dubbed "flying ant day".

The forecaster said the winged insects are usually picked up at this time of the year over the space of about a week.

"Every year around this time we do pick them up on the rain radar. At the moment it's harder to tell because we've got so many showers and the ants look like showers," Simon Partridge, a Met Office forecaster, said.

"They can be seen several miles across. On Friday it was about a mile.

"It's generally the southern parts of the UK where we tend to notice it most. When we do get the rain, they don't fly as much."

He said no swarms had been picked up on Saturday due to wetter weather.

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Flying ants are spotted when males and new queens leave the nest to mate, with many colonies doing so on the same day.

They can be seen on as many as 96% of days between June and September, according to the Royal Society of Biology.