Storms can be a driver's worst enemy
If you really do have to go out in a heavy rainstorm, there are a few things you need to keep in mind.
In cases of severe flooding, you should reconsider making the journey at all. If it is unavoidable, and you have to drive through deep water, it's recommended that drivers take some precautions.
What to do:
- Plan your journey. Is there a route with less exposure to the weather and less risk of fallen trees? Choose a sheltered route if you have the option.
- Drive on the highest section of the road and don't begin a stretch if a vehicle is approaching you.
- Leave time and space between vehicles to avoid swamping other cars and pedestrians
- Drive slowly and keep going once you have started. Make sure you have a clear run.
- If you can't see where you are going to come out of the water, such as when approaching flooding on a bend, think twice about starting to drive into it.
- In deep water never take your foot off the accelerator, as this could allow water to travel up the exhaust pipe
- Once you're out of the water, dry the brakes before you need them. The best way is to lightly apply the brake as you drive along for a few seconds, after checking nothing is following you too closely.
In the wind:
- Strong winds can unsettle your car and even change your direction of travel. Grip your steering wheel firmly and also be ready for the effects of the wind on other road-users, particularly motorcyclists and flat-sided vehicles like lorries.
- Strong winds are not constant, they are usually gusty so ensure you hold the steering wheel firmly.
- Overtaking high-sided vehicles or driving past buildings can result in a sudden gust from the side as you clear.
- Give cyclists, motorcyclists, lorries and buses more room than usual. They get blown around by side winds easily. Even pedestrians can be blown about.
- Watch trees and bushes on the roadside - their branches can show you how strong the wind is.
- Look well ahead, that way you don't need to take your eye off the road and you can see any windy patches before you get to them.
- Keep an eye on what is happening to other vehicles - where they are affected will give you a pre warning.
- Go slow enough to cope with the gusts. Wind can get under a car and reduce its handling and braking significantly.
- Go slowly enough to cope with the tree that has fallen right across the road, just round the bend where you can't see it.
- Be careful of debris, try and have space beside you in case you need to dodge it.
In the rain:
- Before you set off, set your heater controls. Rain can make the windows mist up in seconds. You don't want to be fiddling with controls when you should be concentrating on the road.
- See and be seen - put your lights on. As a rule of thumb, whenever you need to use your wipers you should also turn your dipped headlights on.
- Before overtaking put your wipers on their fastest setting.
- Keep your eyes on the road ahead and plan your driving so that you can brake, accelerate and steer smoothly - harsh manoeuvres will unbalance the car.
- Slow down. In rain the stopping distance is at least doubled. Giving yourself more space also helps to avoid spray, especially when following a large vehicle.
- If you have cruise control, avoid using it on wet roads - you need to pay more attention to the road conditions and alter your speed gently.
These are some of the most frequently asked questions.
How deep is dangerous for a car?
- It's best to avoid flooded roads altogether. If you can't and the water is more than 15 centimetres deep - that's about a third of the way up your wheel - don't attempt it. If the water is up to the car's sill, it could be deep enough to float it.
How do I measure the water's depth?
- Usually the crown of the road is the highest spot. If you can't see the road markings look for familiar indicators such as the water line on kerb stones, a fence or wall.
What if I'm not sure how deep the water is?
- If there are no vehicles already in the water and no indicators to enable an educated guess, don't risk it. Flood water can rip up, carry and deposit all kinds of debris so you might be driving into a deep depression - in more ways than one.
How fast should I drive?
- Less is definitely more in safety terms. Enter the water at no more than 5kmh to 8kmh. First gear tickover may be faster than this so you need to slip the clutch in order not to go too quickly and you you might need to hold the car back if it's an automatic. Keeping the engine revving prevents water entering via the exhaust pipe."
Why so slow?
- You need to push the water aside, creating a depression in front of your car to prevent the engine sucking in water through its air intake. The faster you go the more the water is disturbed and the more likely it is to flood your engine.
What about other cars?
- The waves from other cars, particularly if they're going too fast, will cause the water to become choppy and increase the risk of flooding your car. If you can, wait for others to pass through the section of road and for the water to calm down."
And once I'm through?
- Gently apply your brakes to remove excess water from the pads.
What if the engine sounds strange afterwards?
- It might have swallowed some water. Driving a misfiring car could cause more damage. Stop immediately and seek expert advice.
What if I break down out in the water?
- Put your hazard warning lights on and get out of the car. If that means letting water in, the upside is it could prevent the car from floating and being swept away. Lock the car and go for help.
How can I prepare for driving in very wet conditions?
- Check your wiper blades. They should clear the screen efficiently and have a uniform wiping edge with no breaks in it.
- Make sure your battery is in good condition. If you have any doubts, your mechanic or car dealer can perform a simple test to check it.
- Examine your tyres. They should be in good condition, at the correct pressures, and with ample tread. The legal minimum for tread may be less but we'd recommend you change them at 3 millimetres.