Rain restores the natural order of a very British bank holiday break

There is a long-standing tradition that dictates British bank holiday weekends should be spent either stuck in traffic or sheltering from the rain. So after the chaos on the roads on Friday and the blistering start to the weekend on Saturday – when the hottest August bank holiday temperatures for 25 years were recorded – the weather deteriorated dramatically yesterday.

The temperature in Brighton dropped to 12C (54F) as beach-goers dashed to find cover from a thunderstorm that struck at midday.

Drivers were forced to use headlights by 1pm on the M2 as black skies caused traffic chaos on Kent and Sussex motorways.

In Dover, radar systems belonging to coastguards were struck by lightning. "We saw a massive fork of lightning come down and there was an almighty bang," said a coastguard spokesman.

But meteorologists said yesterday's washout was merely a blip and predicted warm weather again for today.

A spokesman for the Met office said: "While there were thunderstorms in the South-east on Sunday, the weather remained very pleasant in the North. We expect it to be much fresher on Monday but dry and with lots of sunshine."

The good weather is expected to hold out at least until Wednesday.

Yesterday's downpours were a sudden departure from the glorious sunshine of Saturday, when the temperature in London reached 32C (90F), the highest temperature in Britain on that day since the long hot summer of 1976. As millions of people decided to make the most of the weather to get away from it all, Somerset, Devon and Cornwall and the South Coast were inundated with visitors.

Motorists heading for the South-west were caught in 30-mile tailbacks on the M5 on Saturday. The M4 also suffered from severe congestion as thousands made their way to the Reading festival.

Jams caused by the holiday exodus were made worse by a string of road accidents.

Three people were killed when their car smashed into an electricity pylon by the side of the A127 in Rayleigh, Essex, early yesterday.

The road was closed for nine hours while electrical engineers shut down power to overhead cables.

In a separate incident, an 11-year-old boy going to the shops to buy a carton of milk for his mother was mown down and killed by a hit-and-run driver on Saturday morning. Paul Mennie was struck by a car as he crossed the road near his home in Rochdale, Greater Manchester and catapulted into the path of a Transit van heading in the opposite direction.

There were more traffic problems when an articulated truck carrying glucose rolled onto its side at the A13 slip road near Tilbury Docks, in Essex, spilling some of its load on Saturday night.

The driver survived but Essex Police said yesterday that the section of road could be closed until this evening while the road is repaired.

A spokeswoman for AA Roadwatch said: "There were jams on most of the main roads on Saturday as people set off on their breaks. It was much quieter on Sunday but we expect it to get much worse on Monday as people head home.

"We would advise people to leave extra time for their journeys. If it is hot again, they should also make sure they have plenty of drinks with them in case they get stuck in traffic."

Holidaymakers in Somerset had more to contend with than poor weather and traffic conditions when a hay barn caught fire, forcing the evacuation of the popular Mill Farm Holiday Centre in Fiddington.

A 13-year-old boy was arrested on suspicion of arson after more than 40 firefighters worked for more than eight hours to stop flames spreading to a toilet block and shop.