The Institute of Advanced Motorists says drivers should take extra care in downpours.

As wintry weather begins to set in across the UK, the Institute of Advanced Motorists (IAM) has urged drivers to take extra care in wet conditions.

The organisation has issued guidance to motorists, advising them to change their driving style as the rain comes down and increase their safety margins.

In dry, warm conditions, the recommended separation between vehicles is two seconds, but the IAM advises drivers to double that for wet conditions and ten times as much when the roads are icy.

The IAM has also advised motorists to check their windscreen wipers and to turn their lights on when the wipers are operating, regardless of whether the car has automatic headlights.

Cars drive through flooded road in Sidcup UK

And if there's a substantial amount of standing water, the organisation has warned drivers to be aware of the dangers of aquaplaning (when the car's tyres can't clear the water quickly enough and a layer of water forms between the tread and the road).

If your car does aquaplane, the IAM says you should take a firm grip of the steering wheel and gently ease off the accelerator, while making sure not to make any sudden steering inputs.

Car driving through flooded road near Nunney in Somerset UK

Should the road be completely flooded, however, the guidance is to stop before entering the water - particularly if you are unsure as to its depth.

If possible, the IAM suggests taking another route, but if not, you should find out how deep it is. As a rule of thumb, the IAM recommends avoiding water deeper than six inches, but some cars can pass through deeper water using the proper technique.

British motorway traffic at night in the rain with police car

In a manual car, this involves 'slipping’ the clutch to control speed while keeping constant pressure on the accelerator to keep water out of the exhaust pipe.

For those driving automatics, meanwhile, the advice is to keep pressure on the accelerator while controlling speed with the brake.

And if all that sounds too complicated, or if you're in any doubt as to the water depth or the road surface beneath the water, the final piece of guidance is to avoid the flood altogether and turn back.

Car driving through Scottish Highlands near Lochinver on a foggy day

Richard Gladman, head of driver and rider standards at the IAM, said: “With the British weather the way it is, we should all be well practised at driving in the rain. Keeping your car maintained and the rubber (wipers and tyres) in good condition will help you stay safe. In the recent extremes, we have seen that standing water and floods are becoming more commonplace, so take extra care and if possible avoid driving through standing water. If you’re in any doubt about the depth or surface underneath a flood, then it’s best not to take any chances.”