Thunderstorm warnings remain in place for large parts of the UK after heavy downpours and flash flooding brought disruption to roads and railways.
The Met Office has issued yellow thunderstorm warnings until Monday, with the potential for flooding and damage to buildings from lightning and hail.
Severe thundery showers are expected in parts of Wales and southern England on Friday, following stormy scenes and sweltering temperatures across parts of the country this week.
Heavy rain which lashed southern England on Thursday afternoon forced parts of the M25 to be closed, while passengers were evacuated from a train which became stuck following a landslide in Kent.
The Roads Policing Unit for Surrey Police tweeted the M25 was closed between junction six and eight to allow authorities to pump water off the road and allow those trapped on the hard shoulder to make their way through.
Meanwhile, 19 people were evacuated from a train which became stuck following a landslide, according to British Transport Police.
The train came to a halt between West Malling and Borough Green in Kent and rescue attempts were hindered by localised flooding, Network Rail said.
The M25 remains CLOSED between junction 6 and 8 due to this flooding.@HighwaysSEAST have managed to pump enough water to get the hard shoulder running, so those trapped in the closure will slowly make their way through.
Police are now resuming and HE will continue to deal. pic.twitter.com/mGRYaMF4hh
— Roads Policing Unit (RPU) – Surrey Police – UK (@SurreyRoadCops) August 13, 2020
A tweet by Network Rail Kent and Sussex said teams would be working overnight to clear mud which was washed onto the railway by torrential rain in the area.
Devon and Somerset Fire and Rescue Service said on Twitter it had received numerous calls relating to flooding in properties in Devon, with some residents reporting up to 18 inches of water inside their properties.
Six flood alerts, which mean flooding is possible, were issued by the Environment Agency for parts of the West Midlands, including the River Blythe in Warwickshire.
Hammersmith Bridge in the capital was closed to pedestrians and cyclists after safety inspectors said cracks in the the 133-year-old structure worsened during the heatwave.
Temperatures were cooler on Thursday compared to the rest of the week, with the mercury reaching 29.8C (85.6F) in Porthmadog, Wales.
It was the first time temperatures have not gone above 30C (86F) in seven days, according to the Met Office.
Overnight into Friday, there is a further risk of storms across the south, particularly in the West Country and South Wales, while conditions are likely to remain humid.
Met Office forecaster Matthew Box said: “Although we’re unlikely to see overnight temperatures stay above 20C (68F), apart from maybe in London, most places will see temperatures in the high teens for the majority of the UK, particularly in the south.”
A yellow thunderstorm warning issued for Friday covering Wales and much of England has been extended until midday on Saturday, with further thunderstorms expected.
It will be a cloudy start for many on Friday, particularly across central and eastern England.
Towards the west, including Northern Ireland, north west England and western Scotland, Friday is likely to be another day of sunshine, according to Mr Box.