Headlights off or on in bad weather?

21:24, Dec 16 2012
Doing without wet weather lighting in these conditions is stupid.
WET WEATHER LIGHTING: Doing without it in these conditions is stupid.

My father always told me that when it rains you should put your lights on as well as the wipers.

I have always seen his point, because apart from sun showers, there is hardly an occasion when visibility does not deteriorate badly when rain comes.

We have had some grey, wet days recently throughout the country and it struck me during television footage of such weather, especially during the tornado near Auckland, how few people bothered to put their car lights on.

Those who did shone out from the dull, ill-defined blobs that non-illuminated cars become in such conditions.

The problem is that as well as becoming difficult to see, such cars without lights make it more difficult for other road users to judge their distance and closing speed, which is important whether you are using a road on two or four wheels or crossing it on two legs.

Sidelights are no good and, in fact, they are possibly even more dangerous than no lights.


At least someone without lights has no doubt about his or her invisibility or lack of definition, while someone driving with just sidelights on may think the car can be seen, when the little side bulbs' glow is only detectable long after their ill-defined silhouette has loomed into view.

So dipped headlights it should be in dull, wet weather and don't forget that fog lights are for just that: fog. Don't worry if someone flashes their lights at you if you illuminate the car when it's not night time - at least they have seen you.


On the subject of bad weather, British tyre retailer Kwik Fit published some interesting statistics this week about winter tyres (as opposed to snow tyres, per se).

Winter tyres are made from a specially formulated rubber compound and have a tread pattern designed to give improved grip, traction and better braking in conditions when temperatures are less than 7 degrees Celsius. That is not freezing, you understand, but a temperature often experienced around New Zealand, even in the so-called winterless areas.

Tests have shown that when it is colder than 7C, winter tyres will stop 4.8 metres shorter on wet roads and 11 metres shorter on icy roads at 35kmh.

As with mainland Europe, Canada and the northern-most states in the United States, it appears the British are getting into having two sets of tyres - one for winter and one for the rest of the year. They either store them themselves or have tyre depots do it for them.

In the long run, it doesn't cost that much more, because a used car with an extra set of wheels and tyres will always sell before one with a single set, and when it does sell, it will also be worth more to both the buyer and seller.

Also, with two sets taking the brunt of your driving, they wear out half as quickly.

The Press