Motorists have been warned to take care when driving as road conditions remain treacherous during the continuing cold spell.
Tonight is expected to be another very cold night as temperatures are forecast to reach -6C in some places with widespread severe frost and ice.
Severe snowstorms and low temperatures across continental Europe over the last four days have been blamed for 80 deaths.
The toll including 42 people, mostly homeless, who died in Poland last weekend. In France, 12 people have died this month in the severe cold, a homeless group said.
Met Éireann's Harm Luijkx said the weather here will get slightly milder on Christmas Day. “In places where there is snow at the minute, temperatures could drop as low as -8C tomorrow night,” Mr Luijkx said. “It’s certainly very extreme. The lowest we’ve had is around minus 10 on record.”
Minister for Older People Áine Brady today urged the elderly to take extra care during the current cold spell.
“While it can be expensive to heat the whole house, it is important that those rooms in use should be heated," she said.
“It is possible to conserve energy and eliminate draughts by keeping internal doors closed to keep heat in the living area, and by draught-proofing external doors and windows.”
The Minister also advised neighbours to check on their elderly relatives.
Gardaí and AA Roadwatch have warned motorists to be extra vigilant and drive with extreme care as icy conditions remain a problem for much of Munster and Connaught especially on secondary routes.
Chief superintendent Aidan Reid said: "The low temperatures are adding an extra risk for road users, please ensure all the windows on your vehicle are clear and frost free before you begin your journey, leave sufficient time for your trip, and drive at an appropriate speed for the conditions.
AA Roadwatch warned drivers to exercise particular care on the N22 at Macroom, Killarney and the N18 at Ennis. The N5 Swinford bypass also remains icy and it has started to snow in the area. There are treacherous conditions on the N16 Sligo to Enniskillen road between Blacklion & Glenfarne and on the N3 between Cavan and Virginia.
Extremely treacherous road conditions have been reported on the Frenchpark/Castlerea Rd (R361) in Co Roscommon, with motorists advised to avoid the Castlerea/Lough Glynn Road (R325) and the Castlerea/Ballaghaderreen Road (R293) which are both blocked.
There are also reports of bad conditions on higher ground especially on the Killakee Rd (R115), the Wicklow Gap and Sally Gap, Glencree and Roundwood. The hill from Enniskerry up towards Glencree is impassable.
Flights are operating as normal following the recent disruption with only standard delays reported at Dublin, Cork and Shannon airports.
Bus Éireann has said it is experiencing disruption and slight delays to some services. Several Limerick city services are affected, with delays on services between Limerick and Shannon.