Four 15-year-old girls were struck by lightning as thunderstorms caused travel chaos across London.
West London was the worst hit by the rain
One of the girls was taken to hospital in a critical condition after being hit in Hyde Park in London.
In Hammersmith, west London, there were reports of huge hailstones cracking windows.
The Metropolitan Line was also hit with closures between Watford and Moor Park due to flooding. Floods on the A40 have closed the Hanger Lane underpass.
In the west of the city, the District Line was shut between Turnham Green and Richmond.
At Rayners Lane, Metropolitan services were suspended and Piccadilly Line trains were unable to stop at the station.
Commuters faced a struggle getting home
The Central Line between North Acton and Northolt was suspended due to seven inches of flooding at Acton.
Waterloo station was closed due to overcrowding and North Ealing, Rayners Lane and West Brompton Tube stations are still closed because of flooding.
One of the worst hit areas was Harrow in north-west London where thunder and lightning was accompanied by torrential downpours which lasted several hours.
Roads in the area were flooded and huge traffic jams built up.
A lightning strike in the Lewisham area of south-east London damaged fuses to signals, causing delays to trains in and out of London's Charing Cross and
London Bridge main line stations.