Road and ferry transport has been disrupted by adverse weather conditions.
The Stena Line express sailing on the Dún Laoghaire to Holyhead route at 1.15pm was cancelled, as was the Irish Ferries swift crossing on the Dublin to Holyhead route at 2.30pm.
Both ferry companies said services tomorrow are in doubt because of expected rough seas.
All P&O fast ferry sailings between Larne, Co Antrim, and Cairnryan in Scotland have been cancelled because of rough seas, although passengers will still be able to travel on conventional ferry sailings.
Met Éireann says snowfalls in some parts will be followed by further snow and temperatures close to zero overnight.
Ulster, the midlands and north Leinster have borne the brunt of the rain, sleet and snowfalls.
Treacherous road conditions
Road conditions in the midlands have deteriorated after heavy showers of sleet throughout the afternoon.
Gardaí have warned motorists to take extreme care as there is flooding on sections of the M6 and M4 motorway.
There have been a number of minor accidents and heavy sleet is making driving conditions dangerous with poor visibility reported in parts of Offaly and Westmeath.
Roads in the Mullingar area are being monitored by Westmeath County Council employees. While the main roads are currently passable, council gritting teams are on standby in case of any further deterioration in the weather.
The temperatures also dropped to -1C in some parts of the midlands. Road conditions in Donegal and Wicklow are also poor.
Following heavy snow and rain in Northern Ireland, the PSNI is describing roads there as treacherous particularly those in north and west Ulster.
There are reports of heavy snow in the Omagh and Dromore areas of Co Tyrone, on the Glenshane Pass between Derry and Dungiven and in the Maghera area near the Sperrin Mountains.
There is also a warning that heavy rain could cause flooding in some areas.
More information: Met Éireann | AA Roadwatch
