Drivers urged to press one button in their car on Tuesday

Leading experts say motorists are at risk of being slapped with an eye-watering £5,000 fine for forgetting to press one car button on Tuesday. Joe Parry, a spokesperson at online driving instructor marketplace EzLicence, stressed that not turning on the air conditioning and keeping a car well-ventilated could be against the Highway Code.

The specialists warned that intense heat is likely to lead to “drowsiness” which could become a safety issue for road users behind the wheel. The Code makes it clear that staying ventilated and cool was the best option in sweltering heat with the hot weather continuing into Tuesday. According to the Met Office, Temperatures in London are expected to hit up to 34 Celsius today before the intense heat heads South into mainland Europe.

Joe said: “The warmer weather is bound to heat our car's interior. However, few realise that Rule 237 of the Highway Code states that vehicles must be ventilated in the heat to avoid drowsiness.

“So, keeping the window open when possible or using the air conditioning is essential, especially if you’re sitting in traffic.”

A charge for careless driving could see drivers slapped with fines between £1,000 and £5,000, depending on the severity of the offence.

However, courts can impose anywhere between three and nine penalty points and even a temporary driving disqualification.

Rule 237 of the Highway Code states: “Keep your vehicle well-ventilated to avoid drowsiness. Be aware that the road surface may become soft or if it rains after a dry spell it may become slippery.

“These conditions could affect your steering and braking. If you are dazzled by bright sunlight, slow down and, if necessary, stop.”

However, Tim Rodie, Motorpoint's resident driving expert, stressed that motorists should take precautions when cooling down their vehicle before a journey.

Drivers desperate to cool their cabins may leave their car keys inside the ignition with the engine running, making their car a target for thieves.

Tim added: “Modern air-conditioning will cool your vehicle down quickly, so there isn’t really a need to let your car cool down before starting your journey.

“Not to mention that most car insurance policies have ‘keys in car’ or ‘vehicle left unattended’ clauses that mean motorists aren’t able to make a claim if their vehicle was stolen while unattended with the keys inside.

“If you notice that your air-conditioning feels less powerful than normal, you should get it checked out as you’ll still be using fuel to power your air-conditioning system even if it isn’t working properly.”