Different Weather Conditions Introduction

Different weather conditions can lead to a variety of different hazards, both from season to season and from region to region.

You will have to learn to deal with the changes in conditions as the more extreme they are, the more they will test you as a driver.

The best thing to do when there is extremely bad weather is to stay off the road, only going out if absolutely necessary. This will leave the emergency services free to deal with real emergencies, and not attending to stranded motorists.

If you do have to drive then you should make sure you are properly prepared, both with your vehicle and your driving skills.

Severe Weather Conditions

Weather Conditions Your Vehicle

Make sure your vehicle and equipment are in good condition and regularly checked and serviced, whatever the weather.


You should check your tyre condition and pressure frequently, at least weekly, if possible. Make sure that they have a good tread (minimum of 1.6mm over 3/4 of the breadth of the tyre and for the full circumference) and that the side walls, inside and outside, are undamaged.

Also check for uneven wear of the tyre as this may indicate a mechanical problem e.g.. steering off track. Don´t wait for the bad weather before checking as it may be too late by then.

Your tyres are the only thing in contact with the road- look after them!

Keep your brakes maintained and in top condition. Stopping takes much longer on wet, slippery roads, even with perfect brakes.
Wipers and Washers

Make sure your wiper blades are clean and efficient, they should not smear the glass. This is particularly dangerous at night.

Make sure the washers are working and keep the reservoir topped up. Use a good screen-wash. It helps

  • to prevent freezing in winter
  • to clear dead insects and smears and maintain full visibility.
Think ahead

Weather Conditions See And Be Seen

The biggest single danger to any driver is being unable to see properly. If you can´t see the road properly, how will you know what´s coming up next?

Misting Up

If your mirror, or glass inside the car, mists up you may be unable to see properly. Even in the summer sudden rain showers can cause condensation to build up.

  • Keep a dry cloth handy for cleaning all inside glass
  • Wipe the windows dry before setting off.
  • Know how to use your demisters. Use front and rear heated screens early.
  • Open your windows, or use air-conditioning, if necessary.

Warm, dry air works best for clearing condensation but you may have to allow time for the engine to warm up.

Icy Weather

When the weather is particularly icy, your windscreen and windows may be frozen over.

Give yourself plenty of time to clear the screen, making sure that all of the windows are fully cleared before setting off.

Take care not to damage your wiper blades, they may be frozen to the windscreen.

Do Not

  • use boiling water to clear the windscreen; you could break the glass
  • clear just a small space to "peek" through; you need to see everything.

Use dipped headlights in poor visibility (such as rain, drizzle, mist or poor light) so that others can see you.

Use fog lights when visibility is below 100 metres. Make sure that you switch them off when visibility improves as rear fog lights may dazzle the driver behind, even in daylight. They may also make brake lights less noticeable.

Poor Visibility

Weather Conditions Driving On Wet Roads

Wet roads reduce tyre grip, so give yourself plenty of time and space for slowing down and stopping. Keep well back from other vehicles.

On wet roads, you should allow at least double the braking distance for a dry road. Keep a four-second gap.

Remember that after a spell of dry weather, rain can make the surface even more slippery. So take extra care when cornering or turning.


When driving at speed, a great danger in very wet weather is the build-up of water between the tyre and the road surface. As a result your vehicle actually slides forwards on a thin film of water as your tyres lose contact with the road surface. Even good tyres cannot grip in this situation. This is called aquaplaning.

If the steering suddenly feels very light, it could be an indication of aquaplaning.

If you are aquaplaning you should slow down by easing off the accelerator. Do not brake, or try to change direction, as you have no control at all over steering or braking.

The higher your speed on a wet road, the more likely you are to aquaplane. Keep your speed down and watch for water "pooling" on the road surface. Be careful, even at lower speeds. If the front and rear tyres on one side of the vehicle hit a patch of deeper water, the vehicle may "snatch" and swerve because of the additional resistance on that side.

Your Brakes
Water can also reduce the effectiveness of your brakes. You should allow for this and test your brakes when it is safe to do so.

Another reason for keeping your speed down is the amount of water thrown up by other vehicles, particularly larger vehicles. Overtaking, or being overtaken by, these vehicles can be an unnerving experience for the new driver.

Even with the wipers working at full speed you may find that they, sometimes, are not enough to keep the windscreen clear. This may cause a temporary blinding to the conditions ahead.

If water sprays up under the bonnet, it can stop the engine or affect electronics. Think what would happen if you threw a cup of water over a switched-on toaster. Water and electricity don´ mix very well.

Dealing With Floods
When you have to pass through a flood, take your time. Don´t just drive into it- STOP and assess how deep it is. Sometimes roads likely to flood have depth gauges, so check them.
Deep Water

If the water seems to deep for your vehicle, turn back and go around the flood by another road. It might take a little longer, but that´s better than finding yourself stranded in a flood.

If the water is too deep it could

  • flood the exhaust causing the engine to stop
  • find it´s way into the air intake on some vehicles, causing serious engine damage.
Shallow Water
If the water is not too deep, drive through slowly, but be sure to keep to the shallowest part. Remember, because of the camber of the road, the water will probably be deepest near the kerb and shallowest at the crown.
Driving Through Floodwater

Drive in first gear as slowly as possible but keep the engine speed high and steady by "slipping" the clutch.

  • If the engine speed is too low you might stall.
  • If you go too fast, you cold create a wave, flooding the engine and cutting it out.

Try to strike a balance.

Consider Pedestrians
Pedestrians can easily get drenched by passing vehicles. Look well ahead and show consideration by slowing down or giving them more room when it´s safe to do so.
Engines And Water

Some types of diesel engine will tolerate a certain amount of water, but many fuel systems are electronically controlled and are, therefore, affected by water.

All petrol engines can be seriously affected by even small amounts of water being splashed onto the electrical components, such as engine management systems, coil, distributor, leads and so on.

When You´re Through

Once you are safely through, check your mirrors before testing your brakes.

If they do not work properly, it will help to dry them out if you apply light pressure to the brake pedal while driving along slowly.

Do not drive at normal speed until you are sure that your brakes are back to normal.

Crossing A Ford

A Ford is simply when running water crosses the road.

The depth of water at fords varies with the weather and is usually greater in winter.

There may be a depth gauge.

If the water is not too deep for your vehicle, cross using the same technique as you would for a flood. Remember to test your brakes after you cross. There may even be a notice to remind you to do so.


Don´t try to displace the water by "charging" at the flood or ford.

  • You could lose control.
  • Your vehicle will probably stall.
  • You could end up blocking the road.
Water On Roads

Weather Conditions Driving In Crosswinds

Some vehicles may become unstable in strong crosswinds, because of their large surface area and comparatively low weights. This can happen particularly on exposed stretches of road such as motorways, viaducts and bridges.

The effect can vary from a pull on the steering wheel to a distinct wander, possibly into the path of another vehicle. In very bad cases, the whole vehcle can be lifted bodily off the road, with very serious results.

Cyclists & Motorcyclists
In gusty conditions, watch for cyclists or motorcyclists being blown sideways and veering into your path. Allow extra room when overtaking.
High-Sided Vehicles

Drivers of high-sided vehicles, or those towing caravans, trailers, horse-boxes, etc., particularly empty ones, should

  • pay special attention to the forecasts of strong winds
  • avoid well-known trouble spots and high bridges.

Drivers of these vehicles should be constantly alert for the effects of wind near bridges and embankments, even on normal journeys in reasonable conditions.

Other drivers should beat this in mind when about to overtake, or when being overtaken by these particular vehicles.


Weather Conditions Driving In Fog

Fog is one of the most dangerous weather conditions. An accident involving one vehicle can quickly involve many others, especially if they are driving too close to one another.

Motorway pile-ups in fog have sometimes involved dozens of vehicles. All too often, there's a los of life or serious injury, which could easily be prevented.

Observe The Obvious


  • If the fog is very thick and you can see the rear lights of the vehicle ahead, then


Avoid Driving In Fog

Take alternative transport or postpone your journey, if at all possible.

If you must drive, give yourself time to prepare, check all lights, clean your windows and windscreen, and so on. Allow moretime for the journey.

Fog Patches
The density of fog varies. Sometimes the fog is patchy. One moment it can be fairly clear, the next extremely dense. Avoid the temptation to speed up between the patches
Use Of Lights In Fog

Correctly adjusted fog lights can be a valuable aid when driving in fog.

In Daylight

You must use your dipped headlights or front fog lights when visibility is seriously reduced.

They'll be seen from a much greater distance than sidelights.

They won't dazzle other drivers or pedestrians in the daytime.

Use fog lights if your vehicle is fitted with them.

At Dusk
Use dipped beams at dusk and other times when visibility is poor.
At Night
In darkness, you might need to depend entirely on fog lights, or alternate between fog lights and dipped beams, through stretches of thick and thin fog.
High-Intensity Rear Fog Lights

If your vehicle has high-intensity rear fog lights, use them in fog only when visibility is seriously reduced. Normally this means when you cannot see for more than 100 metres (328 feet).


  • You must switch them off when visibility improves- it is the law. Using them at other times, such as in the rain, can dazzle following drivers and make your brake more difficult to see.