Monday could be the hottest day of the year so far after more than a month’s rainfall deluged parts of Birmingham in just one hour on Sunday.

Thunderstorms and heavy downpours swept across the country on Sunday, causing flash flooding that left a major route into Birmingham impassable because of water up to 5ft deep.

The Met Office said a site at Winterbourne, in Edgbaston, recorded 58mm of rainfall in just one hour on Sunday afternoon, and 81mm in a 12-hour period.

People make the most of warm Sunday evening weather on Sunday at Emsworth Mill Pond, part of Chichester Harbour (Flora Thompson/PA)
People make the most of warm Sunday evening weather on Sunday at Emsworth Mill Pond, part of Chichester Harbour (Flora Thompson/PA)

The monthly average for the West Midlands region in May is 55mm, meteorologist Craig Snell said.

But he said the torrential rain had been “very localised”, pointing out that another site 10 miles away at Coleshill recorded just 3mm of rain in 12 hours.

The heavy downpours could continue for some on Monday, with a yellow weather warning for rain in place as thunderstorms roll south through Northamptonshire, Buckinghamshire and Berkshire overnight.

Mr Snell said: “We won’t see the scenes we saw last night.

“There could be a few very short-lived thunderstorms but overall it will be a much quieter night.”

In the West Midlands overnight a person was rushed to hospital after they were rescued from the roof of a car submerged in floodwater.

Paramedic Peter Bowles said members of the West Midlands Ambulance Service’s Hazardous Area Response Team swam to the vehicle to treat two people who were on top of it.

Once brought to dry land by boat one of them was taken to A&E, he said on Twitter.

Southern England was struck by lightning between 15,000 and 20,000 times on Saturday night into Sunday morning.

The Environment Agency has more than 20 flood warnings and more than 40 flood alerts in place covering much of Central England.

A yellow weather warning for rain is also in place from the afternoon for large swathes of East Anglia, the South East including London, the South West and Wales.

But Mr Snell said temperatures could hit highs of 28C or 29C in the South East, potentially surpassing the 2018 record of 29.1C on April 19 in St James’ Park, central London.

People feed goslings from pedalos on the Serpentine in Hyde Park, London (John Stillwell/PA)
People feed goslings from pedalos on the Serpentine in Hyde Park, London (John Stillwell/PA)

He said: “It all depends how much cloud develops. There’s a chance we could see the warmest day of the year.

“It will be quite widely into the 20s across many parts of the UK.

“For a bank holiday Monday, it’s not looking too bad.

“Further thundery downpours might appear in the late afternoon – not everyone will see them but if you do see one they could be quite nasty.

“The areas worst hit on Sunday might escape.”

Scotland would see the most prolonged sunshine, he said, but most areas would start dry and cloud cover quickly burn off.