Driving in Adverse Weather Conditions

Adverse weather conditions - Fog

As adverse weather conditions go, fog does not seem to pose too much of a threat

Do not be luled into a false sense of security. You can enter a fog bank either from the outside in which case it will be patchy. Patchy fog is dangerous. You have reasonable visibility then all of a suden nearly none. Alternatively a fog bank can evolve around you. This is a strange experience the first time that it happens to you and one that you should be wary of.

Fog does not always stay in one area as a continuous sheet. It does get patchy before you are clear of it altogether. If you have driven through some thick fog and it appears to be getting thinner do not be fooled. It can just as easily get thicker again as clear up.

Window Demisters: Use your demisters even if it only covers the rear window. Anything that helps with effective observations is good.

Windscreen Wipers: Turn your windscreen wipers to their intermitent setting. Keeping the windscreen clear is very important.

Mirrors: Make regular use of all mirrors. It is important that you maintain effective observations at all times.

Driving Lights: Your driving lights should be switched on. Do not be tempted to put your lights onto full beam. The fog acts as a mirror and you will dazzle yourself. The correct setting is to have your driving lights dipped.

Fog Lights: Fog lights should only be used if visibility is reduced to below one hundred metres. There is no other acceptable reason for turning on fog lights.

Visibility: Visibility whilst driving through fog is going to be variable and you can not afford to make any assumptions.

If fog is combined with another adverse weather condition such as snow or ice then your problems are compounded. Not only do you not know what is ahead of you, you do not know exactly how effective your tyres are going to be at any given point along the road. In this circumstance it is much better to play safe and drive very slowly and in a low gear.

Visibility in fog changes as has already been mentioned. Even if you think that you have cleared the fog you might still be in for a suprise around the next corner.

The height of the road can be a discerning factor in how thick the fog is. Imagine fog as a cloud that came to ground level, which in some cases is exactly what it is. If the road that you are on stays level then your visibility through the fog will remain similar, apart from at the edges where it will fluctuate. Imagine for me if you will that the road takes an uphill slant. As your car ascends the fog will begin to thin because you are climbing out of it. Great, but do not be tempted to accelerate just yet. There is a slight dip ahead of you, and unbenown to you the dip is followed by a downhill gradient. Voila! You are back in the thick of the fog.

Patience is the key to driving in any adverse weather condition. Take your time and get there safely. Would the people who may be waiting for you prefer you to be late or not get there at all? A solemn question but a valid one.

What is Fog?: Definitions vary but the essence is the same. Here are a couple of definitions of fog:

1) Condensed water vapor in cloudlike masses lying close to the ground and limiting visibility. according to the 'Math/Science Nucleus'.

2) droplets of water vapor suspended in the air near the ground according to 'WordNet'.

Fog is basically a normal cloud but at ground level. A bank of fog can be formed in different ways.

3) 'Wikipedia' can usually be relied upon for a decent definition and offers this: Fog is cloud in contact with the ground. It occurs when moisture from the surface of the Earth evaporates; as this evaporated moisture moves upward, it cools and condenses into the familiar phenomenon of fog. Fog differs from clouds in that fog touches the surface of the Earth, while clouds do not.

If you have an interest in what the different types of fog are and how they are formed then I suggest you follow the link above to Wikipedia. I feel that the different causes and compositions of fog are beyond the scope of this piece.

Remember the golden rule when driving in areas of diminished visibility. Always drive at such a speed that you can safely stop in the area that you can see to be clear.