How To Drive In Heavy Fog Conditions

Last Updated: 10/04/2021

As we’ve explained in other guides on this website, weather conditions are among the most hazardous outside influences or environmental factors that you can be affected by while driving.

Once such condition is fog and mist, though sadly many drivers totally underestimate how dangerous and problematic it can be.

In short, fog can be a killer!

It can descend quickly and reduce visibility to a terrifying few metres.

Even on the roads you know best, fog can be a great equaliser and take away any familiarity or safety cushion you thought you had.

Hazards or obstacles can be just yards away from you.

Driving in fog is about minimising the risk to yourself, to pedestrians and to other road users.

It is crucial therefore that you can see other vehicles and they can see you.

Fog lights need to be used at the right times to combat reduced visibility otherwise you could be a danger to yourself and other motorists.

Increased stopping distances are also going to be vitally important while the speed at which you’re driving should be significantly reduced.

What You Will Learn

Driving in the fog can be scary, especially for new and inexperienced drivers.

It can also panic or catch-out people who have been driving for years if they are not careful or perhaps have not driven in foggy conditions for some time, so it’s well worth taking the time to read this guide.

We’re going to try and give you all of the information and advice you need to make your next foggy drive a safer one.

Step-By-Step Guide
Video Demonstration
Hints & Tips
Useful Information
Final Thoughts
Further Resources

Step-By-Step Guide

Our step-by-step guide for driving in the fog is more of a checklist and list of hints and tips to ensure you’re giving yourself the best chance of driving safely as possible.

So, here is the guide to driving in fog:

It is highly advisable to check your lights before setting off. This obviously includes your fog lights. Depending on the make, model and age of your car, you may have fog lights at the front or back, and you may have multiple on the front.
Make sure you’re familiar with how to operate your front and rear fog lights before setting off, and don’t confuse these with your vehicle’s ‘full beam’ setting.
Before entering fog you should slow right down and check your mirrors.
Keep a good distance between your vehicle and the vehicle in front.
Keep your windscreen wipers going and make sure your windscreen is clear by using the demistifier.
If you see the word ‘FOG’ on signposts ahead but the road looks clear, don’t assume that the sign is wrong. Fog can come down in patches and take you by surprise. Reduce your speed and be vigilant.
If visibility is reduced to the length of a football field (Highway Code – Rule 226) then you must switch your lights on. You should know where your main switches are, particularly the fog light switch before you begin any journey.
Do not put your full beam on as the fog reflects the light back and your visibility will be reduced even further.
Do not be tempted to use the tail lights of the vehicle in front as a means of navigating your way through the fog.
Driving through fog safely is not just about using your eyes it is also important that you open your windows at junctions and crossroads and listen carefully. If visibility is very limited, wind down your windows at junctions and crossroads to allow you to listen out for approaching traffic.
It is important to know that mist is very different to fog. In addition, sometimes conditions can change to what is known as freezing fog.
You can significantly compromise yourself and others in your vehicle or on the road if you do not use your fog lights when needed.
Insurance companies may refuse to pay out if you are involved in a road traffic accident and not using your fog lights.
As soon as fog appears you should switch on your fog lights and leave them on until the flog clears and the road returns to normal. Do not keep switching your fog lights on and off as this may cause confusion for other drivers trying to navigate their way through the fog.
During the autumn/winter season when there is more chance of fog it is key to ensure your car is in the best running state to tackle the conditions before it, meaning it is highly advisable to check your lights are working before setting off.

Video Demonstration

Hints & Tips

It is a legal requirement that all cars must have rear fog lights fitted.

Front fog lights are not a legal requirement but it makes sense to use them if you are unable to see very far.

Top Tips For Driving In Foggy Conditions:

Use fog lights when you need to.
Keep a greater distance – allow three seconds between you and the car in front.
Beware of other drivers not using headlights.
Use dipped headlights, wipers and demisters.
Don’t rely on automatic lights – they may not come on in fog.
Don’t rely on ‘daytime running lights’ alone – they only light the front.
Drive as fast as conditions will allow and no more.
Relying on another car’s rear lights to assist you through the fog is dangerous.
Keep your speed down so that you give yourself plenty of time to stop if you need to.
If a vehicle is too close behind you increase your speed slowly to widen distance between you but don’t speed up to widen the distance as this can be dangerous.

Final Thoughts

If you have to drive in fog, then do so by excising a lot of care and taking your time.

Like driving in other weather conditions, such as heavy rain or ice, it’s about driving safely and getting to your destination in one piece.

If it takes longer, so be it, it’s a small price to pay.