London thunderstorms alert: Extreme weather forecast as millions swelter in rare September 'tropical night'

London could be swept by thunderstorms this morning as the capital swelters in warm and humid conditions.

BBC Weather has forecast thunderstorms between 9am and 10am as rain falls on the capital after another dry spell.

It comes as temperatures are expected to rise to 25C or 26C this afternoon.

On Tuesday, the capital reached a high of 28C as unusually warm late-September weather took hold over the southern England.

Muggy conditions saw a rare September “tropical night”, with the temperature staying above 20C all night in London, according to the Met Office.

In London temperatures reached an astonishing 21.8C at 2am, according to the Met Office.

Meteorological X account @TheSnowDreamer posted that the “historically late” tropical night is “unknown for time of year”.

“Still needs to be confirmed Heathrow fell just short 19.9C but seems inner London, St James’s Park stayed above 20C,” it added.

Speaking on BBC Radio 4’s Today programme, BBC Weather’s Chris Fawkes predicted “heavy bursts” of rain.

He said: “We’ve got an unsettled start to the day. Low pressure to the north-west of the UK is driving across the country.

“For many of us it’s going to be a wet start to the morning.”

The South-East had a “very mild” start to the day with the temperature in Essex as high as 21C at 6am.