Parts of the UK could see a month’s worth of rain in just a few hours as a thunderstorm warning has been increased to amber.
The Met Office issued the warning until 9pm on Saturday – with flooding and power cuts likely.
It comes after temperatures reached 32.2C in Surrey, making it the hottest day of the year so far.
Those within the warning area could see 50-60mm of rain in a short period of time, and some might see 100mm in a few hours – which would be equivalent to a month’s worth.
The warning means “fast flowing or deep floodwater is likely, causing danger to life”, it says on the Met Office website – and people within the amber area have been urged to take care.
Dan Stroud, meteorologist for the Met Office, said: “We’ve got quite an intense area of thunderstorms that has developed over the West Midlands this afternoon and it’s moving northwards.
“Some spots could see 100mm in a few hours and that’s equivalent to a month’s worth, and considering it’s been so dry now there could be some impact as after it’s been dry the ground’s ability to soak up rain is impeded.
“People need to take care when they’re out on the roads and if possible just avoid travelling until it has cleared.
“The area of storms is quite intense.”
It comes as the Charlotte Edwards Cup final between Southern Vipers and the Blaze was suspended on Saturday evening following heavy rain in Worcester, with play set to resume at New Road on Sunday’s reserve day.
The amber thunderstorm warning has been issued after a yellow warning was initially announced for Wales and a large part of southern and central England until 9pm on Saturday.
A second yellow warning for thunder is in place for Sunday from midday to 9pm for Wales, Northern Ireland and most of western and central England and Scotland.
On Sunday, there is likely to be more cloud – with slightly cooler temperatures, the forecaster added.
More hot weather is expected next week, with thunder and showers on Monday – but by Tuesday onwards it is likely to settle.
Most of the UK will meet heatwave criteria next week, the meteorologist said.
The UK Health Security Agency (UKHSA) has issued an amber alert for hot weather until 9am on Tuesday in the West Midlands, East Midlands, east of England, South East and South West.
It means the impact of the heat is “likely to be felt across the whole health service… and the wider population, not just the most vulnerable”.
A further yellow alert, which is less serious and warns that there may be some disruption to services due to weather conditions, is in place for the North East, North West and Yorkshire and Humber regions of England, as well as London.