A yellow thunderstorm warning has been issued by the Met Office, with flooding and disruption possible in parts of England and Wales.

More than half a month’s worth of rain could hit some areas, with 40-50mm falling in one to two hours, the Met Office said.

The warning comes into force at noon on Monday and lasts until 10pm, covering most of Wales, the West Midlands, and many southern English counties.

It comes as a 42-year-old man’s body was recovered on Sunday after searches for a swimmer who was reported missing from Loch Ard, Trossachs national park, at 9pm on Saturday.

Police Scotland’s diving and marine unit were involved, along with a mountain rescue team and an air support unit. There are not thought to be any suspicious circumstances surrounding the death.

On Sunday afternoon, showers started to hit the Reading and Bristol areas, with more severe thunderstorms expected to develop on Monday, Met Office meteorologist Becky Mitchell said.

Mitchell said: “It’s another hot and humid day across the southern areas and that’s going to trigger thundery showers.

“On Monday between 20mm and 30mm of rain could fall in an hour and between 40mm and 50mm in the space of one to two hours.”

Hail and localised power cuts, as well as flooding and disruption, are a possibility within the warning area depending on how long the heavy showers linger, she said.

The average rainfall in May is 70mm, so some areas could see more than half the month’s worth of rain, the forecaster added.

Northern Ireland could see some heavy rain on Sunday night and the north-west of England and southern Scotland could see scattered showers on Monday afternoon, but the same level of impact as the warning zone is not expected.

From Tuesday onwards the weather is forecast to turn more settled, and Northern Ireland and Scotland could see their hottest days of the year so far, Mitchell said.