Drivers are being warned to be aware of treacherous road conditions, as low temperatures make way for frost and ice.
The Road Safety Authority is asking drivers to slow down, and says black ice is likely in many areas.
It's also advising motorists to check vehicles for any damage that might have been caused by recent storms.
Brian Farrell from the RSA, says the cold weather follows weeks of rain.
"Coming on top of all the severe weather we've had recently, flooded roads and wet roads, it really does add to the dangers that drivers face out there - and this applies to really all parts of the country - please be mindful of the changing conditions."