Met Éireann has issued a weather warning for this weekend and early next week.
Showers of sleet and snow are forecast in many areas with widespread severe frosts leading to icy roads.
Temperatures are forecast to drop to -4C overnight and possibly to -7C over the weekend.
AA Roadwatch has already been dealing with dozens of breakdowns on icy roads. The Road Safety Authority is urging road users to take extreme care.
The severe weather warning from Met Eireann has prompted Age Action to urge people to make an extra effort to keep in contact with their older neighbours in the coming days.
Elsewhere, driving winds and sub zero temperatures have brought blizzard conditions to parts of Britain.
Southern and eastern England have been the worst affected areas with disruption to some air travel as well as to road and rail networks.
Forecasters have issued warnings for further heavy snowfall this morning in London, the East Midlands, Yorkshire and Humberside.
Flights into and out of Luton and Gatwick airports were suspended for a time this morning.
A spokesman for Heathrow Airport said the runways were cleared through the night.
Conditions are expected to ease during the course of the day but further snow is predicted over the weekend.
