Roads were blocked and hundreds of homes flooded or left without power by the storms.
In Essex the fire brigade was inundated with calls from Harlow, Epping and Ongar. 'It's as if the whole of the Harlow area is under water,' a fire brigade spokseman said. Sixteen crews were working through the night to pump out homes.
A contraflow system introduced on the M11 near Harlow after the surface broke up in the heat was awash with water.
In north Wales, hundreds of homes were flooded when rivers overflowed. A police spokeswoman said emergency services were swamped with calls for help after a thunderstorm moved over the area.
There was chaos in parts of Gloucestershire as more than 11 2 inches of rain fell during another brief thunderstorm.
At Cirencester, an inquest had to be adjourned because the noise of the storm was so loud witnesses could not make themselves heard.
Storms in Worcestershire left more than 30,000 homes without power.
An hour of torrential rain brought chaos to roads in north Devon, with up to 5ft of floodwater blocking the main A386 Bideford-Torrington road.