The cold snap continues with widespread frost nationwide and a risk of icy patches in places. Snow showers will affect parts of Ulster, Connacht, Munster and parts of the midlands with accumulations of 2cm or 3cm expected.
Tuesday night will see temperatures fall to minus 5 degrees.
Drivers are asked to exercise caution as icy conditions have been reported around Wicklow and Wexford towns, Waterford City and Tullamore.
There are also frosty road conditions around Carlow town and on the back roads around Naas.
The Conor Pass in Co Kerry is closed until further notice due to the poor weather.
In Co Cork, there is snow around Fermoy, Mitchelstown, Castlelyons, Ballyhooly Mallow and Buttevant and snow is also affecting roads around Roxboro, Castletroy and Bruff in Co Limerick.
Motorists are advised to avoid any steep inclines around Ballyhoura, Ardpatrick and Kilfinane.
Icy conditions have been reported around Clonmel and there is heavy snow on the M7 Limerick/ Dublin Road between J27 Birdhill and J23 Moneygall.
Snow is sticking to roads around Roscommon town and in Carrick-on-Shannon and Manorhamilton in Co Leitrim.
Due to a snow at Southampton Airport in the UK, some flights to and from Dublin Airport have been cancelled.
Large variation
Met Éireann has said temperatures varied by 20 degrees across the island of Ireland last month with one of the warmest New Years on record giving way to freezing temperatures towards the end of January. Some areas experienced their wettest January on record.
In its monthly weather bulletin, Met Éireann revealed that the 1st and 9th of January were exceptionally warm in many places, with temperatures hitting 16 degrees at Oak Park in Carlow, and almost 15 degrees at Shannon Airport.
Dublin Airport got the best of the sunshine, and had its second sunniest January since records began in 1971. On the other hand, Knock Airport experienced its wettest January since records began there 22 years ago.
Windiest January
It reflected a largely wet and windy period for western counties, with gusts of 130 km/h recorded at the Mace Head meteorological station in Co Galway.
The report says that most stations had their windiest January in recent years, with some in western areas registering their highest average wind speeds for this time of year in over two decades.
The lowest air temperature was logged at Dunsany in Co Meath on the 19th - minus 6.2 degrees. Met Éireann’s readings don’t account for snowfall depths, which reached upwards of 10cm as the weather took a cold turn towards the end of last week.