DRIVING in the fog is one of the most dangerous times to be on the road. Let us understand why fog hinders driving.

Fog normally occurs during winter when the days are warm and the nights very cold. During the day, the ground heats up and retains the heat. As night falls and temperature drops, the air becomes heavy and dense and falls to the ground which is warm. This difference in temperature causes vapour in the air to condense. You begin to see the air. This is fog. It should not be confused with mist, which is an entirely different phenomenon of nature. This fog can be almost about 20 to 30 metres thick. Meteorologists refer to this as ground fog.

It is entirely possible that a tall structure like the Qutab Minar may have its top sticking out in bright sunshine from a vast white blanket of cloud which stretches from Amritsar to Allahabad. Aircraft cannot land or take off. Flights have to be rescheduled to afternoon hours. That would also be the best time for you to be driving.

As the day progresses and the sun heats up the ground again, the hot air close to the ground rises and the fog or dense air begins to dissipate. By mid-day, fog usually disappears.

Fog can reduce visibility to a bare 5-10 metres. This is no time to be at speed. The first defensive action to take while driving in the fog is to reduce speed.

There are some very definite do’s and don’ts to be observed while driving in the fog.

As mentioned, reduce speed immediately and if necessary shift into a lower gear. Be ready to brake suddenly. Obstacles on the road show up without notice. Drive at a speed so that you can stop in the distance covered by your vision.

Check your rear-view mirror. Is the driver behind you too close on your tail? He may not be keeping a safe distance. If you feel unsafe, tap your brakes a couple of times to alert the driver following you. If necessary put on your hazard flashers.

Do not attempt to overtake. This could be a suicidal move. Indian drivers are known to drive on the wrong side of the road, attempting a short cut. Well, there’s no fun running head on into another vehicle on a cold foggy day.

Do stay in your lane. Use the white lines as markers and at no time should you cross an unbroken yellow line to enter the other lane. Avoid this at all costs, or else you’ll face traffic head on.

Drive on low beam. High beams of full headlights blind the drivers coming from the opposite side. It also hinders and reduces your own visibility. The strong white lights are not capable of penetrating the opaque blanket of fog.

Do have your wipers and windscreen washer functioning properly. Fog lights, which are yellow, are definitely a help.

Very important. Do familiarise yourself with your car. I see that even the new breed of cars have the windscreen and rear window all misty. The red lines of the electric heater are clearly visible through the white condensation on the rear glass. Just press a button and it will be clean in no time. The trick is to find where this button is. It is just as simple to clear the windscreen. Read the owner’s manual, learn about the comfort, luxury and the safety your car provides.

Happy motoring!