Driving safely in fog, rain, snow, and poor-visibility conditions

It's often hard to avoid driving in reduced visibility, such as at night or during rain. Photo: Getty

What is ‘poor visibility’?

Rather than using your imagination, the term ‘poor visibility’ has a clear and quantifiable definition: the National Road Safety Partnership Program (NRSPP) defines ‘poor visibility’ as when “road users are not clearly visible at a distance of 100m due to unfavourable conditions”.  

Common winter weather conditions like rain, fog and snow can cause poor visibility, but it’s not just the colder months you should be wary of.

Sun glare, smoke and dust can also cause poor driving visibility, and can be experienced year-round.  

And that’s not to forget driving at night, where your visibility is only as good as your headlights and the surrounding streetlights – of which there may be none depending on the road you’re travelling. 

“Motorists should also remember that vulnerable road users such as pedestrians, cyclists and motorcycles are much more difficult to see in low visibility conditions,” Morris says. 

“Those who do not adjust their driving to suit the conditions not only put themselves at high risk of an accident or injury, they are also risking the lives of others they share the road with.”

You can make poor visibility even worse if  your windscreen is dirty or your wipers aren't functioning properly. Photo: Getty

Tips for driving with poor visibility

The best way to stay safe when low visibility strikes is to avoid driving if possible. If it’s not a necessary trip, consider delaying your journey until conditions improve.

If that’s not feasible here’s some tips for how to drive more safely with poor visibility.

Increase your distance, decrease your speed

Morris says that several factors, including visibility conditions, can impact the amount of time it takes for a driver to react once they see a hazard on the road, meaning drivers should increase their distance.

“For example, if it is raining, add one second to the minimum of three seconds, making a total of four seconds,” says Morris. “If it is raining and visibility is also impaired, then add another second making the minimum five seconds.”

Morris adds that there isn’t a set amount you should reduce your speed by during poor visibility conditions, but it should be enough that you can keep the aforementioned amount of distance in front of your car without creating a hazard for other motorists. 

Keep your windscreen clean

It seems obvious, but having a clean windscreen will help with visibility. A dirty windscreen can even scatter light and make glare worse. For crystal-clear results, try using glass cleaner and microfibre cloth.

Check your windscreen wipers regularly too, and make sure they’re not leaving streaks (this is a sign they may need to be replaced). 

Don’t let your car fog up

Be familiar where your demisters are in your vehicle and check where they are before you start driving in a new vehicle. You can also use your car’s air conditioner to clear foggy windows, or even open windows to let the cold air clear the windscreen as a last resort.

Use your high beams correctly

When visibility drops, it might feel instinctive to turn on your high beams to help see, but using them in the wrong conditions can make visibility worse or blind oncoming traffic.

For example, using high beams in fog scatters more light back at you, making visibility worse. Instead, use your fog lights if you have them, or dim your headlights if you don’t. The same principles apply to driving in smoke, which acts similarly to fog, as well as in snowy conditions. 

High beams should be reserved for when you’re travelling on a dark road with no oncoming traffic, such as a country road. If you see a vehicle coming towards you, dim your high beams so you don’t blind the other driver. 

Blinded by the light

Incorrect use of high beams as well as sun glare can cause temporary blindness while driving.

You’re more likely to be affected by sun glare during the early morning and evening when the sun is low in the sky. If driving at these times, be prepared by adjusting your sun visor and keeping a pair of polarised sunglasses handy. 

Do not look directly into another car’s high beams. If you see an oncoming vehicle that has forgotten to dim their high beams, use the lane markings on the left-hand side of the road to guide yourself until the other vehicle has passed. If a car with high beams on is behind you, adjust your rear vision mirror to reduce the glare.

In the event you are blinded, slow down and pull over if safe to do so until your vision is fully restored.

Know when to pull over

If visibility worsens to the point that you can’t see past your bonnet, put on your hazard lights and pull over as soon as safe to do so. Do not continue driving until visibility returns. 

The information provided is general advice only. Before making any decisions please consider your own circumstances and the Product Disclosure Statement and Target Market Determinations. For copies, visit racv.com.au. As distributor, RACV Insurance Services Pty Ltd AFS Licence No. 230039 receives commission for each policy sold or renewed. Product(s) issued by Insurance Manufacturers of Australia ABN 93 004 208 084 AFS Licence No. 227678.