The RSA is warning motorists to take extra care this evening due to the added risk posed by freezing fog and icy roads.

Temperatures are expected to drop as low as -5 degrees in many areas tonight, as Met Eireann has issued an orange weather warning.

As visibility is reduced in such conditions a collision involving one vehicle can quickly involve many others, especially if driving too fast and too close to one another.

The greatest risk is of a multiple-vehicle pile-up on roads with higher speeds such as motorways and dual carriageways.

Dense fog reduces visibility greatly and makes driving very dangerous. However freezing fog, when liquid fog droplets freeze to surfaces, can make it difficult to keep the windscreen surface clear.

The RSA has issued the following advice:

Pedestrians and cyclists are advised to:

• Avoid going out in dense fog / freezing fog unless it is a necessity. If absolutely necessary make sure you are clearly visible by carrying a torch and wearing reflective clothing. Stay well in off the road where there is no footpath when vehicles are approaching.