Britons are braced for a week of thunderstorms, flash flooding and heavy rain as the UK faces a sixth day of sweltering temperatures during a historic heatwave.
A yellow storm warning has been issued for the whole of England, Wales and areas in Scotland by the Met Office, meaning those regions could see flooding and power cuts from Wednesday afternoon until the end of the week.
Thunderstorm warnings are in place until Monday, with heavy rain, lightning and hail expected, the Met Office said.
Forecasters have also warned of potential damage to buildings from lightning strikes or strong winds and a chance of travel disruption due to flooding.
It comes as the Met Office confirmed the current heatwave is the first time since 1961 that the UK has seen six consecutive days of temperatures above 34C.
As soaring temperatures are set to continue in southern England on Wednesday, chief meteorologist Paul Gundersen said the hot weather has created ideal conditions for thunderstorms.
The temperature has now reached 34.6C at St James's Park#Didyouknow that this current #heatwave is the first time since at least 1961 that we have had 6 consecutive days of 34C and above#UKHeatwave pic.twitter.com/y8xVfWlV1J— Met Office (@metoffice)August 12, 2020
"Today, warnings cover much of England, away from the east coast, Wales and parts of Scotland," he said.
"The storms will be isolated but where they happen there will be frequent lightning, gusty winds and intense, heavy downpours with 30 to 40mm of rain possible in less than an hour and, in isolated spots, a small chance of 60mm falling.
“With the continuing hot weather large swathes of the UK continue to be at risk from thunderstorms and potentially the impacts from heavy rain, into the early part of next week.”
hail stones the size of ice cubes in London right now pic.twitter.com/3KA6ENAi1f— Jim Pickard (@PickardJE)August 12, 2020
Greg Dewhurst, a Met Office forecaster, told the Standard: "We will probably see quite severe thunderstorms in southern parts of England and Wales tonight, which could move up into western parts of England overnight.
"We could see some hail, frequent lightening and heavy rain tonight. We could see some flash flooding in places. We could see as much as 40mm of rain falling within one hour.
"It's been very hot today - all the ingredients are there for thunderstorms. They will continue through the night."
On Thursday, Mr Dewhurst said there will be some lingering thunderstorms from the previous evening.
"They should gradually fade away and turn brighter," he said.
"We are looking again at warm sunshine - not quite as hot as the last few days have been - but temperatures in southern England could still reach low thirties.
"As the day goes on, we will see an increase in risk of thundery showers once more, particularly across England and Wales."
— Sofia Petkar (@SophiePetkar)August 12, 2020
He added: "For the weekend, it continues on a similar note.
"We have warnings right through the weekend for thunderstorms."
It comes after torrential rain and lightning lashed large parts of Scotland causing flooding and travel disruption on Tuesday evening.
Perth and Kinross, the Lothians, Forth Valley and the north east were among the most affected by overnight lightning strikes and heavy downpours.
The Scottish Fire and Rescue Service confirmed it was called to multiple reports of flooding in the Perthshire area, affecting many properties.
— Eva Murray (@TriMyData)August 12, 2020
Vehicles were recovered from busy roads after they were abandoned and there were reports of internet services being disrupted.
Drivers in the UK have also been warned of delays on the roads caused by standing water.
Ben Sheridan, an AA spokesman, said: “Rain, thunder and lightning combined with the hot weather will make for some challenging driving conditions.
Thunderstorm warnings continue across much of the UK until Monday, 17th August, with a risk of impacts from heavy rain, flash flooding, lightning and hail.
Check out the latest details: https://t.co/CbPXkqdk1L pic.twitter.com/6iUnL3xHBE— Met Office (@metoffice)August 12, 2020
“Don’t be misled by the sunshine – if you ignore flood warning signs, there’s a real risk of aquaplaning or causing serious damage to your car.
“Drivers need to be wary of slippery road surfaces when approaching junctions and roundabouts.
“When it first rains during dry periods, build-up of deposits such as oil and rubber on the road which haven’t been washed away makes the road surface greasy and harder to stop on.”
Neil Davies, Flood Duty Manager at the Environment Agency, added: "Isolated thunderstorms could bring sudden surface water and river flooding to parts of England today, which may lead to flooded properties and severe travel disruption in some areas.
"Further surface water and river flooding is also a possibility from Thursday to Sunday."