After a very mild start to the New Year temperatures are set to plummet as low as -3 degrees tonight, Met Éireann has forecast.
Motorists have been warned to be prepared for icy roads and hazardous conditions with widespread frost expected.
‘This sudden drop in temperature, combined with wet road surfaces across the country will result in extremely hazardous conditions for drivers,” Aoife Carragher of AA Roadwatch said today.
She noted that motorists “have not had to deal with the usual icy January driving conditions”.
She advised motorists to slow down as “speed is the greatest hazard on icy roads”.
Tonight “frost and icy patches will form as well as dense fog patches in the light winds.” Met Éireann has said.
Tomorrow will also be cold and frosty to start with “fog lingering for some time", Met Éireann said.
Ms Carragher also warned of black ice which “very often forms on wet roads”.
“Drivers will need to be extremely careful tonight and tomorrow morning especially on exposed bends, underneath trees and on higher ground. These are the places where a skid is most likely to happen,” she said.
"Freezing fog is also a possibility; fog lights should be used in affected areas and switched off again afterwards,” Ms Carragher said.
Met Éireann noted that it would feel “much cooler than of late” during the day tomorrow with highs of just 5 to 9 degrees. However it will even colder in areas where the fog remains.
Tomorrow night will see a “sharp to severe frost” and some icy patches with temperatures as low as -4 degrees.
The cool weather looks set to continue for the rest of the week with temperatures increasing to between 8 and 12 degrees from Sunday.
The Road Safety Authority (RSA) urged drivers to be particularly aware of the risk of black ice on roads. "If the road looks polished or glossy it could be black ice, one of winter's worst hazards," said an RSA spokesman.
"Black ice is difficult to see. It is nearly transparent ice that often looks like a harmless puddle or is overlooked entirely. Watch out for black ice, especially in sheltered or shaded areas on roads, under trees and adjacent to high walls."
The RSA also called on anyone setting off on a journey in the coming days to check up-to-date weather forecasts, make sure their vehicle windows and mirrors are cleared, lights are working, tyres are checked and to slow down and drive gently. Motorists were also warned to be on the look out for vulnerable road users such as pedestrians, cyclists and motorcyclists.