The day before, London recorded its hottest June 12 when the thermometer rose to 90F (32.3C).

But by yesterday morning thunderstorms had swept in from Brittany and battered the South-east and the Midlands – giving them a taste of the weather endured by much of the rest of England on Monday.

Homes in Dartford and Swanscombe in Kent were struck by lightning and some suffered floods 2ft deep.

In London, the fire brigade was besieged with calls after shops, houses, roads, multi-storey car parks and basements were swamped by the sudden afternoon rainfall that turned the sky black. Gareth Harvey of the PA Weather Centre said: "It was caused by the transition between humid weather and cooler, fresher conditions."

The Met Office forecast is for more of the same, with most areas staying warm, and a risk of showers for the next two days in the South. Temperatures will start rising in time for the weekend.

Heavy rain also swept across parts of Yorkshire and the North-east last night. It followed heavy downpours on Monday as a cold front moved in from the Atlantic to clash with hot air from the Continent.

The weekend heatwave claimed a victim yesterday when a father died in hospital two days after being swept off an inflatable dinghy by a wave. Terry Woodward, 42, from Shrewsbury, was with two of his children off Borth in Ceredigion, Wales. He and one child toppled from the inflatable, but while the child scrambled back, Mr Woodward was swept away. The two children returned to shore and raised the alarm.