Drivers are being warned to expect long delays this weekend as nearly 13 million getaway journeys are planned.
The RAC said around 12.6 million leisure trips by road will take place between Friday and Monday, causing “bumper-to-bumper traffic”.
The majority of schools in England and Wales break up for summer on Friday – which is set to be the worst day for congestion as holidaymakers embark on day trips or holidays by car.
Traffic hotspots will include the M5 south from near Bristol (Junction 15) to Bridgwater (Junction 23), which is a popular route for holidaymakers travelling to the southwest, according to Transport analysis company Inrix.
There are also likely to be delays on the M25 clockwise between Junction 10 for the A3 to Kingston and Junction 6 for the A22 to East Grinstead, it predicts.
Drivers wanting to avoid long queues are advised not to travel on major roads between late morning and early evening from Thursday to Sunday.
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RAC spokesman Rod Dennis said routes heading south and west are likely to encounter some of the longest queues.
“Anyone using the M5 southbound from Bristol should anticipate bumper-to-bumper traffic, with those travelling outside peak periods most likely to have a better journey,” he said.
“We’re seeing an enormous increase in breakdowns this year as drivers dependent on their vehicles for leisure and work contend with cripplingly high prices, leading to some scrimping on car maintenance as a result.
“It’s for this reason we’re urging drivers to take action to avoid a summer surge of breakdowns.
“No driver should set off before a long journey without carrying out a few basic checks to ensure their cars have got the right levels of oil and coolant, as well as making sure all tyres have plenty of tread and are properly inflated.”
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Read more:
How the heatwave will impact your holiday
Gatwick strikes: What you need to know if you’re going on holiday
Full list of rail and Tube strike dates and services affected
Meanwhile, holidaymakers sailing from the Port of Dover are being warned to expect two-and-a-half hour delays this week during the peak hours of 6am to 1pm during the first couple of Saturdays and Sundays of the summer holidays.
The port is urging car passengers embarking on summer getaways from Friday to arrive up to three hours before their booked sailing.
Port of Dover chief executive Doug Bannister said his staff have done “everything we possibly can” to minimise delays – and warned unforeseen circumstances such as technical issues, industrial action or road traffic accidents on the approaches into the port “could throw us some more challenges”.
UK airports are also expected to be busy – though hundreds of thousands of flights across Europe this summer are in jeopardy following a vote by air traffic controllers to take strike action.
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Almost 1,000 workers at Gatwick Airport, including baggage handlers and check-in staff, will stage eight days of strikes from later this month.
Budget airline easyJet announced earlier this month that it had been forced to cancel 1,700 flights during the peak summer holiday season in response to the impact of air traffic control strikes in Europe and knock-on effects of the closure of airspace due to the Russia-Ukraine war.
In addition, the heatwave gripping Spain, Italy, Greece and Europe’s other most popular holiday destinations is impacting people’s getaways, with some British holidaymakers cancelling or changing their travel plans due to the extreme weather conditions, with forecasters predicting even higher temperatures this week.
