Drivers are being urged to check their tyres before beginning journeys on “searing Saturday”.
The AA is concerned the start of a weekend when millions of people will be making long trips to the seaside, football matches, music festivals and holidays will coincide with extreme heat.
Temperatures are expected to peak at 35C, increasing the risk of blowouts for tyres that are inflated to the wrong pressure or already damaged.
The wrong tyre pressure can mean dangerous tyre blowouts— Sean Sidley, AA
Motorists should also consider having their vehicle’s cooling system checked by a mechanic as overheated engines are a common cause of breakdowns in hot weather, according to the AA.
Radiator cooling fans are more likely to seize on older cars, meaning they will not work when needed, potentially leading to costly engine damage.
AA patrol of the year Sean Sidley said: “Having your car break down would be torturous in the heatwave this week, so drivers should take steps to prepare their car before they set off.
“Peak temperatures are expected over the weekend when many will be travelling longer distances, whether that’s to the beach or visiting friends and family, and hot weather brings more problems with engines overheating and tyre blowouts.
“It’s best to set off at the coolest part of the day to reduce the risk of your engine overheating.
“Equally, the wrong tyre pressure can mean dangerous tyre blowouts on hot summer days when road surface temperatures increase, so check the pressure regularly.”
RAC spokesman Simon Williams said: “Drivers should carry plenty of water, melt-proof snacks, a hat or an umbrella for shade, sun block and a fully charged mobile phone in case of an unexpected breakdown.
“Being stuck at the side of a road in these extreme temperatures without shade or protection could be very dangerous.”