The Met Office has issued a travel warning to anyone using roads across the UK this evening ahead of "reduced visibility". The UK weather agency warned motorists to "beware" of fog tonight (Thursday, September 24) when driving because it can impact how well you can see the road and other vehicles around you.
What causes fog
Fog is a weather phenomenon that happens when there is essentially a cloud at ground level, which causes a reduction in visibility to less than 1000 metres. Fog, like clouds, is caused by tiny water droplets suspended in the air, but not all fog forms in the same way and there are a few different types of fog, the Met Office explains.
Dense fog is when the visibility falls below 100 metres, which can cause severe travel disruption. The thickest fogs tend to occur in industrial areas where there are more pollution particles in the air, allowing water droplets to coalesce and grow.
Met Office advice for drivers
The Met Office took to social media on Thursday afternoon, urging UK drivers not to use their full beam headlights, as the fog reflects the light back, which can reduce visibility even further.
"Do not use full beam lights, as the fog reflects the light back, reducing visibility further."
On top of that, the Met Office reminded motorists to ensure they are familiar with how to operate their front and rear fog lights, follow the "two-second rule" or even increase the gap to four seconds. This is to ensure that there is sufficient space between your car and the car in front when visibility is reduced.
Drivers should also have their heater on windscreen de-misting setting and make sure all of the vents are open.
And finally, the Met Office said: "If visibility is very limited, wind down your windows at junctions and crossroads to allow you to listen out for approaching traffic."
Advice for road users when travelling in fog
- Avoid travel if possible
- Drive very slowly with dipped headlights, full-beam lights reflect off the fog causing a 'white wall' effect
- Keep an eye on your speed, fog can give the illusion of moving in slow motion
- Use fog lights, but remember to turn them off when the visibility improves
- Don't hang on the tail lights of the car in front, rear lights can give a false sense of security
- Watch out for freezing fog, which is made of water droplets that freeze on contact with objects such as the pavement, road, car, etc, it can quickly form a layer of ice
