A period of mixed weather is on the way with cooler temperatures and rainy spells likely, the Met Office has said.
Wednesday will see some rain in the South East but then sunny spells across many parts with temperatures beginning to cool, the forecaster said.
There could be heavier rain in the north west of the UK by evening, becoming more widespread on Thursday.
A “plume of rain” moving towards the north west of Scotland could bring some high rainfall totals, especially on high ground, the Met Office said.
Southern and eastern parts of England will remain largely dry and warm, but it could be a particularly windy day for August quite widely.
A mostly dry and clear weekend is expected, but temperatures are not likely to be as high as they were earlier in the week.
A yellow heat health alert for the East and West Midlands, East of England, South East, South West, North West and London, issued by the UK Health Security Agency (UKHSA), will remain in force until 9am on Wednesday.
Liam Eslick, a meteorologist at the Met Office, said: “Temperatures on Wednesday will probably not be as warm as what we’ve had today, probably seeing maximums of around 24C or 25C towards the South East.
“There will be sunshine towards the western half of the UK on Wednesday, so it will still feel rather pleasant, getting up towards those low 20s.
“Into Thursday we do have a second plume of rain moving in towards the north west of Scotland which can bring some pretty strong winds and pretty heavy rain.
“It’s not anything to be concerned about for now, it’s just a watchpoint.
Mr Eslick said there was good news for those with weekend plans, as sunny weather is likely to return.
“It will be a mostly dry picture for many people as we go in towards the weekend, most places will see a pretty dry picture and will start to see some sunnier spells,” he said.