Keep your speed down & your distance long
It’s the golden rule of driving in the rain: adjust for the conditions.
In heavy rains, there are two factors working against you: you can’t see as well, so you won’t react as quickly to finding something in your way in front of you; and once you do hit the brakes, the reduced traction of the wet road will make it take longer to bring your car to a halt.
The single most important factor affecting safe driving on wet roads is speed.
If you’re traveling at 60mph and need to stop in dry conditions, it will take you an average of 90 metres to stop. (For reference, that’s already just a little under the length of a football field.) In the rain, that distance goes up to 122 metres. Do you have 122 metres of visibility in a heavy downpour? Typically, the answer is no.
Slow down to 50mph and your wet stopping distance goes down to a much more reasonable 85 metres, about two-thirds of the distance needed from 60mph
This goes doubly if the rain has just started and the weather has been nice for a while. Unseen substances like rubber and oil can build up on the surfaces of roads, and it takes a few minutes for the rain to wash them off. In the meantime, they can make the asphalt very slick and reduce traction significantly.
And remember that those around you have longer stopping distances as well. A large vehicle like a 4×4 will need far more space to brake with its heavier weight, so cutting one off is an even more terrible idea than usual when the road is wet. Maintain a bubble around you on all sides to ensure that you can stop, the person behind you can stop, and you’ve got somewhere to go on either side in case one of those first two safeguards fail.
Don’t stop on the motorway or use your hazards
It’s not an overly-common misconception, but it’s still out there. That as soon as the rain hits your hazards should be on. It couldn’t be further from the truth!
The only time that hazard lights are intended to be used on a moving vehicle are when it’s part of a funeral procession. Otherwise, you never hit the hazards when you’re driving.
Why? There are a few reasons: the people who know the rules might assume you’re stopped and respond with unnecessary reactions; it actually reduces the ability of others to see your brake lights and indicators; and if someone actually is pulled over, it makes it harder for emergency services to identify and assist them.
The best thing to do when you’re caught in a storm is ensure that your lights are on fully – but not to high beam level. Just flip the switch to on and you’ve done the best you can do for your safety.
Along the same lines, should the conditions get so bad that you feel you simply can’t continue, never stop on a motorway. If you can’t see the car ahead of you, then the car behind you can’t see you, and you’ve turned into an accident waiting to happen. Continue with extreme caution until you reach the next junction, and ideally into a car park if there’s one nearby, and just wait for it to blow over.
Motorcyclists will sometimes make themselves an exception to this rule because it would leave them and their bikes soaked, so they’ll usually stop under motorway bridges instead. It’s not the safest solution but they’re not likely to let that concern them, so be aware that there’s a good chance they’re there and keep an eye out for them whenever you pass under a bridge.
It’s a given, but driving has to have 100% of your attention
When the topic of distracted driving comes up these days, the first culprit most people think of is smartphones. We all know the law, it’s simply not worth it to touch your phone whilst driving, no matter how tempting it may be. Get a hands-free kit or put it in the glovebox.
But there are many other things that can distract us when we’re driving, some of which people don’t give a second thought. It’s important not to let them make you lose focus, especially in weather when your safety requires your full attention.
If you’re talking hands-free on the phone, tell the person you’ll call them back after the weather improves. Calmly let your kids know that you need to focus on driving for your family’s safety and ask them to keep arguments and requests to a minimum until the rain stops. Consider turning the radio down or off so that any sudden sounds don’t distract you. With rare exceptions, these interruptions will only last a few minutes, and they’ll still be there to go back to once the weather improves.
Keep your eyes peeled for standing water & don’t ignore your tyres
In heavy rains, standing water can become a serious safety issue.
The first risk is hydroplaning, which is what happens when your tires can’t adequately wick away the amount of water they’re encountering and keep themselves in contact with the road.
You can help yourself with one aspect of this by regularly checking the tread depth on your tires. Once the treads become too shallow, they can no longer effectively move water away and you’ll need to replace them. The old trick is to take a 20p and place the coin in the main tread channels multiple times, at various points around the tyre. If you can see any part of the outer band of the coin face, it means the tyre tread is too shallow – and probably illegal. It’s not only time to stop everything and replace your tyres, it’s vital that you do so as soon as possible.
Another key aspect of avoiding hydroplaning is one we’ve already discussed: slow down. A reduced speed allows your tires to do the work of moving water out of the way so that they can stay connected to the pavement. The faster you’re going, the more likely it is that the tires won’t be able to keep up and you’ll send nothing but water under the contact patch, causing you to lose traction and, inevitably, control.
Finally, keep your eyes up and watch what other motorists are encountering. If you see a car going through a large puddle, change lanes or take a different route if you can. When things get really bad, be aware of exactly how much water your car can make it through. The measurement you’re looking for is your air intake – if water gets in there, you’re likely to do some damage to your engine. This depth will be different for every vehicle, so know what yours is and work your way through standing water accordingly. If you think you can make it through, go very slowly. If you don’t know, don’t go.
Look after your wipers
Forward visibility is one of the most important safety factors in storm conditions, and on that front there’s only one thing you can affect: your windshield wipers.
The average set of wipers will last between six months to one year depending on things like sunlight, salt, freezing and debris that can cause the rubber to degrade at varying rates.
All you need to know is that as soon as your wiper blades start showing signs of wear by skipping, scraping, pulling away from the frame, or leaving streaks behind, it’s time to buy a new set.