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Safer wet-weather driving

When it snows, most drivers slow down and take extra precautions. But that's not necessarily the case when it rains. Yet driving in any wet weather is considerably more dangerous than driving when the weather is dry. Poor visibility, lower levels of grip and the chance of hitting deep puddles are just some of the problems a driver needs to deal with.

The good news is that modern technology has helped make wet driving safer with developments such as more efficient windshield wipers, better windshield defoggers and tires with enhanced wet-traction capabilities. Even with these improved features, keeping the following tips in mind can improve the safety of your wet-weather driving.

Being seen
The most important factor in safer wet driving is the ability to see and be seen, a point that’s often forgotten. Being seen by other drivers is easy: Simply turn on your low-beam headlights when it rains, even during the daytime. In some states, this is the law. This simple action will allow other drivers to notice your car from the front (headlights) and the rear (taillights). In a really heavy downpour, when you either have stopped on the shoulder or are moving at less than 10 or 15 mph in the slow lane, you should consider turning on your four-way flashers to alert other drivers that you are there. State laws vary about this practice, so check your local driving codes.

Seeing clearly
Seeing out of your vehicle requires several important considerations:
  • Your wipers must be new enough to remove water from the windshield without streaking.
  • Your defogger must be powerful enough to keep the windows clear. Most defoggers use the car's air-conditioning system to help with the process. With some cars, you have the ability to turn the A/C on and off separately from the defroster function. If so, turn on the A/C to help dehumidify and defog, even in the winter. Some cars also have an air recirculation switch. If your car does, make sure that it is set on "fresh air" rather than recirculation. All of these steps will help speed up defrosting.
  • Most rear window defoggers use electrical heating wires on the rear glass. It's common on older cars for a few of these "lines" to become broken, usually from someone cleaning the window too vigorously. In most cases, this can be repaired.
  • At night, use your low-beam headlights to avoid excessive glare from the raindrops. Remember: High beams do not help visibility in the rain.
  • Cleaning the inside of the windshield is particularly critical. The inside of your car’s windshield and window glass must be clean and free from any oily films that may cause bad reflections or distortions as you drive. 
  • If you use an automated car wash, the spray wax can sometimes build up on the windows, causing the water to stick to the glass and making vision a problem. Clean your windows even after a car wash.
Maintaining contact
Your tires are the only contact your vehicle has with the road, and their condition is critical to wet-weather traction. If your tires are worn and the tread depth is below 2 millimeters, you may experience hydroplaning, especially at higher speeds or in deep water.
One way to test the tread depth is to put a penny headfirst into a tread groove. If President Lincoln's head is inside the tread, you still have usable tread left. If you can see Lincoln's entire head, it's time for new tires. Another way to check tire wear is to look for the wear bars molded into the major tread grooves. If the wear bars are visible, the tires are worn. New tires are obviously ideal for wet conditions, since tires loose their ability to shed water as they wear.

Wet-weather driving tips
The way you drive can obviously have a significant impact on wet-weather safety. Be attentive to the situation around you, including what other drivers are doing and how they are reacting to conditions:
  1. Slow down early, before you encounter a problem, and be aware that you have less grip available from your tires for stopping, steering and accelerating. Remember: Even four-wheel drive and anti-lock brakes can't change the laws of physics.
  2. Even a new tire can begin to hydroplane on wet surfaces, so watch your speed. If the steering begins to feel light and the car is splashing through deep puddles, gently reduce your throttle to allow the car to slow to a more manageable speed. Don't lift the throttle abruptly or hit the brakes, since this could unsettle the tires’ grip on the wet surface.
  3. Never drive your car through deep water on a flooded road. You simply cannot tell how deep the water is. It doesn't take much water to disable your vehicle or even float it off of the road surface. If you have any doubt about water depth, stop and go back the way you came. If you must drive through deep puddles, gently press the brake pedal one or two times afterward to help dry the brakes before you need to use them to stop the car.
  4. Use the various speeds on your windshield wipers to help remove the amount of water that is hitting the windshield. This sounds simple, but some people forget that at higher road speeds you need the highest wiper speed.
  5. Be aware of the spray coming from passing trucks and oncoming cars. It may blind you temporarily, so anticipate this by turning on or increasing the speed of your wipers and by looking at what’s happening to cars ahead of you.
  6. If it begins to rain very lightly after a long dry spell, the water will mix with the oils on the road to produce a very slippery surface. Treat these conditions with great caution since even new tires won't give much grip on this oil-and-water mixture.
  7. Turn down the radio and turn off your cellphone. Driving in heavy rain demands much more of your attention than driving on dry roads.
  8. If conditions become too intense, pull far off the road in a safe place to wait out the storm. If your car becomes disabled, pull as far off the road as possible, turn on your four-way flashers and call for help. Stay in your car.
Preparing your car
If you are serious about driving in wet conditions, there are several things you can do to prepare your car:
  • Make sure your wiper blades are like new and that they still have a sharp wiping edge.
  • Clean your wiper blades by running a damp cloth along their edges from time to time to remove the buildup of oils and debris that the wipers have removed from the windshield.
  • Clean the outside surface of your windshield and window glass. Then clean all of the inside glass. Use a commercial product or mix white vinegar and water to squirt onto the windows. Newspaper makes an excellent polishing rag for automotive glass. Just rub until the streaks are gone and the windows are crystal clear.
  • If your windshield is heavily pitted, it might be time for a replacement. Nothing lets you see better than a new windshield.
  • Make sure that your headlights and taillights are working properly and that their lenses are clean.
  • Make sure your tires have sufficient tread and are inflated to the manufacturer's specifications.
Be safe
The biggest factor in safer wet-weather driving is you and your judgment. When visibility drops and the roads become flooded, only you can tell if it is time to pull off and take a break. Sure, it may take you a bit longer to reach your destination, but in the end, the few minutes spent to be safe will be worth it.
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