12 Hidden Dangers to Watch Out for On Hot Sunny Days

Given a choice, every motorist would take driving in summer to winter. Drier weather and lighter nights mean less stress and fewer hazards – perfect for commuters and holidaymakers alike.

But that’s not to say the warmer months don’t bring their own unique risks out on the road. Hot weather can cause a variety of unforeseen dangers, so it pays to be prepared for every eventuality.

Whether you’re planning a summer road trip with the family or simply looking for advice on safer year-round driving, this guide covers 12 hidden dangers to watch out for on hot sunny days.

Hot Weather Car Maintenance

First things first, it’s important to remember that hot weather can affect your car in more ways than you might think. By understanding the dangers, you can prepare in advance and make sure your car is serviced and maintained to deal with extreme heat.

Here are some of the problems that can affect your car in hot weather.

  1. Bulging Tyres and Punctures 

When temperatures rise, so does the pressure of your tyres. Hot weather causes the air to expand, meaning a higher PSI that could take your tyres over a safe limit.

When tyres are pumped up too high, it increases the risk of punctures and can cause bulges in the sidewall. Check your tyre pressure before long journeys and make sure they’re inflated to the right pressure for your load.

  1. Overheating Engine 

Overheating isn’t necessarily a hidden problem, but it’s easy to overlook the condition of the cooling system in summer, believing that winter poses the greatest risks for the engine.

In warm weather, engines run hotter, so the cooling system must work harder to keep things cool. This is especially true during low-speed driving, when the fan isn’t drawing enough air into the radiator to moderate the temperature of the coolant/antifreeze.

In summer, check the level of the coolant/antifreeze regularly and make sure it’s changed in line with the manufacturer’s service schedule.

man on the phone calling for roadside assistance

  1. Clutch Wear 

Hot weather puts strain on most moving parts of your car, including the clutch, which already runs hot due to friction. Extreme heat can cause premature wear of the clutch plate, which could result in a breakdown or a costly repair.

It can be difficult to reduce clutch wear, with driving habits and style partly to blame for any premature damage. Try not to ‘ride’ the clutch when driving at low speeds, and make sure to fully remove your foot from the clutch pedal when you don’t need to change gear.

  1. Flat Car Battery

Both hot and cold weather can affect how well your car’s battery holds charge. This is because changes in temperature impact the chemical processes within the battery’s cells, placing strain on the unit.

In hot weather, be careful about when and how you use electricals, such as the air conditioning. It’s a good idea to switch all these off until you’re up to speed, giving the battery time to charge before additional strain is placed on it.

For more tips and advice on summer car maintenance, read our comprehensive guide on how hot weather can affect your car.

General Safety Tips for Driving in Hot Weather

With the right maintenance, most modern cars should be able to cope well with the demands of hot weather – but the same might not be said of you and your passengers. Hot weather can be hazardous on long journeys, so you need to be prepared.

Here are some common dangers to watch out for when driving in warm weather.

baby in baby seat in back of car

  1. Sunburn Through Car Windows

 While most modern car windows offer some degree of UV protection, this doesn’t mean you should scrimp on sun cream. It’s a good idea to apply a decent UV blocker before taking to the wheel, and that includes all your passengers.

For back-seat passengers, especially children and babies, sunshades are a great addition and can help block UV rays that the windows let through. Still, sun cream is the best line of defence, and essential for young travellers.

  1. Electrical Devices Overheating Inside Cars 

Leave your car in the sun for any length of time on a hot day, and it’s shocking just how high the temperature can climb in the cabin. For this reason, it’s never a good idea to leave electricals inside (though we’d never recommend that anyway, for security) or you could risk frying the battery.

Remove any gadgets, tools, or personal devices from your car when you’re parked up in hot weather. Even a couple of minutes parked at a service station could be enough to overheat some devices, so pack everything away where possible.

  1. Sun Dazzle Through Dirty Windows

Sun dazzle is one of the biggest dangers of summer driving, with the potential to massively reduce all-round visibility. Dirt, smears or abrasions on the windscreen and windows are to blame, causing glare that even the most reliable sunglasses can struggle to reduce.

Keeping on top of cleaning your car is the first step in reducing sun dazzle. Of course, you should also make sure the screen wash is topped up, so you can quickly remove any dirt, dust or residue that may cause visibility problems whilst out on the road.

  1. Glare from Hot Roads

Drive anywhere in hot weather, and chances are you’ll notice glare from the road ahead. This is caused by light refracting off a hot surface and makes the road appear wet, causing a shimmer that can be very distracting in some situations.

As above, always make sure you have plenty of screen wash to reduce glare, and keep those sunnies on hand. Good-quality polarising sunglasses are ideal for hot-weather driving, as they do a great job of reducing glare.

couple driving at evening sunset

  1. Dehydration on Long Journeys

It doesn’t take long to get dehydrated in hot weather. So however short or long your journey, always pack plenty of cold drinks and refreshments to stay hydrated, avoiding symptoms such as headaches and fatigue.

Another thing to mention is hay fever. When it’s hot, the pollen count tends to be very high, so consider this before you set off. Take a non-drowsy antihistamine and keep the windows closed to reduce hay fever, using the recirculated air conditioning setting to reduce the amount of air coming in from outside. 

  1. Farm Traffic on Country Roads

 If you’re planning a family road trip this summer, chances are you’re venturing somewhere rural and remote. And you know what that means: an increase in farm traffic on narrow country lanes.

Summer is a busy time for farmers, with tractors and combine harvesters beavering away close to popular tourist destinations. If you’re driving on unfamiliar rural roads, pay attention to farm vehicles that may suddenly pull out from behind hedges or appear around bends, and give them the space and patience they need.

  1. Holiday-Related Traffic Jams

Hot weather can often trigger a mass exodus to the coast and countryside, meaning you’ll be contending with more traffic than usual. Summer traffic jams can be a real problem for holidaying families, and with more staycations happening this year than ever, you should expect delays and plan accordingly.

Traffic jams aren’t good for either you or your car, with high temperatures making it more likely that both man and machine will overheat. Make sure your car is properly maintained ahead of your trip, and always carry extra water and refreshments in case of seasonal tailbacks.

We hope this guide helps you through a safe summer of driving. For more motoring guides and features, click here for the Prestone blog. Or to browse our complete range of high-performance car maintenance tools and products, visit the homepage.

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