Flash floods have hit many parts of London, causing cars to become submerged. The Environment Agency estimates that 1.4 inches of rain fell in one hour. This is significant because the UK Met Office expects 1.9 inches of rain in the entire month of June. There were also power interruptions in different parts of London.

In South London, flooding in the areas of Croydon, Mitcham and Wallingdon led to entire cars being submerged, with roads going under up to 2 metre of water. Lightning struck several parts of London as well, and the fire brigade said they had to attend to a 30-minute fire.

Grahame Madge, forecaster for the Met Office, said the situation could continue, "What we have is a situation where we have warm, very moist air coming in from the continent and the heat added to the warm air causes it to rise and sees the development of these showers. The intensity of those can be very severe in localised areas – as we have seen in some places like London and Brighton there has been very heavy rainfall."