The town of Falmouth took the brunt of the freak hailstorm.
"It went on for about 20 minutes," Falmouth teacher Tommy Matthews told The Daily Telegraph. "Just when I thought it was over, it came down harder and harder."
Photos of the hail were posted on social media, the Telegraph said, along with other reports of heavy rain and localized flooding. The newspaper said the rain flooded garages, overflowed storm drains and forced the evacuation of a cafe where water inside the building was knee deep.
Weather across Britain was expected to remain unsettled in the coming days but the Met Office, Britain's official weather service, said the storms will be followed by dry and pleasant weather.