The London Fire Brigade were put on stand-by as the Met Office issued a warning for severe thunderstorms and a risk of flash flooding in the capital.

Last night the Met Office predicted that heavy downpours "will start from about midnight and there will also be a lot of lightning".

The expected torrential rain overnight did not materialise but the Met office warned of heavy rain and and localised flooding in London.

"A yellow alert has been issued to highlight the risk of localised surface-water flooding," a Met Office spokeswoman said.

The London Fire Brigade were reportedly ready to deploy fire rescue units complete with inflatable boats in the event of flash flooding.

The LFB's Jim Knighton said: "We're ready and waiting to help people who might be hit by flooding."

"Keeping people safe is our top priority but flooding can also devastate people's properties and possessions, so wherever possible we use sandbags to keep water out of people's homes."

The Fire Brigade warned the public to “put people before property” and to call 999 if in danger.

Six large water pumps have also been are stationed across the capital in case of flooding.

The heavy rain caused signalling problems for Eurostar in France and Belgium resulting in delays of up to half an hour, the BBC reported.

Torrential rain in London as heatwave ends